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楼主: 王守恩

[求助] 数码和是7倍数的n位数

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 楼主| 发表于 2024-11-10 09:00:13 | 显示全部楼层
往前冲一冲!若把“7”改成“71”,  这个矩阵特征多项式会有吗?

点评

有道理!丢了!  发表于 2024-11-10 10:10
理论上也会有,只是美观性复杂性趣味性各方面都没什么了  发表于 2024-11-10 09:50
毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
 楼主| 发表于 2024-11-10 10:10:34 | 显示全部楼层
继续学习!数码和是19倍数的n位数。
这样的1位数有0个。
这样的2位数有0个。
这样的3位数有45个。
这样的4位数有615个。
这样的5位数有4950个。
这样的6位数有42459个。
这样的7位数有461055个。
这样的8位数有4904064个。
......
NestList[Dot[NestList[RotateRight, {1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1},16], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0}, 26][[All, 1]]
这条代码应该怎么调?谢谢!
毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
 楼主| 发表于 2024-11-10 16:08:07 | 显示全部楼层
(01)。数码和是1倍数的n位数。{9, 90, 900, 9000, 90000, 900000, 9000000, 90000000, 900000000, 9000000000, 90000000000, 900000000000, 9000000000000, 90000000000000, 900000000000000}
NestList[Dot[NestList[RotateRight, {10}, 0], #] &, {9}, 14][[All, 1]]

(02)。数码和是2倍数的n位数。{4, 45, 450, 4500, 45000, 450000, 4500000, 45000000, 450000000, 4500000000, 45000000000, 450000000000, 4500000000000, 45000000000000, 450000000000000}
NestList[Dot[NestList[RotateRight, {5, 5}, 1], #] &, {4, 5}, 14][[All, 1]]

(03)。数码和是3倍数的n位数。{3, 30, 300, 3000, 30000, 300000, 3000000, 30000000, 300000000, 3000000000, 30000000000, 300000000000, 3000000000000, 30000000000000, 300000000000000}
NestList[Dot[NestList[RotateRight, {4, 3, 3}, 2], #] &, {3, 3, 3}, 14][[All, 1]]

(04)。数码和是4倍数的n位数。{2, 22, 224, 2249, 22500, 225002, 2250004, 22500004, 225000000, 2249999992, 22499999984, 224999999984, 2250000000000, 22500000000032, 225000000000064}
NestList[Dot[NestList[RotateRight, {3, 2, 2, 3}, 3], #] &, {2, 3, 2, 2}, 14][[All, 1]]

(05)。数码和是5倍数的n位数。{1, 18, 180, 1800, 18000, 180000, 1800000, 18000000, 180000000, 1800000000, 18000000000, 180000000000, 1800000000000, 18000000000000, 180000000000000}
NestList[Dot[NestList[RotateRight, {2, 2, 2, 2, 2}, 4], #] &, {1, 2, 2, 2, 2}, 14][[All, 1]]

(06)。数码和是6倍数的n位数。{1, 14, 151, 1503, 14997, 149991, 1500009, 15000027, 149999973, 1499999919, 15000000081, 150000000243, 1499999999757, 14999999999271, 150000000000729}
NestList[Dot[NestList[RotateRight, {2, 1, 1, 2, 2, 2}, 5], #] &, {1, 2, 2, 2, 1, 1}, 14][[All, 1]]

(07)。数码和是7倍数的n位数。{1, 12, 126, 1282, 12860, 128598, 1285774, 12857176, 128571220, 1285713534, 12857141804, 128571429416, 1285714293398, 12857142874408, 128571428581010}
NestList[Dot[NestList[RotateRight, {2, 1, 1, 1, 1, 2, 2}, 6], #] &, {1, 2, 2, 1, 1, 1, 1}, 14][[All, 1]]

(08)。数码和是8倍数的n位数。{1, 11, 112, 1124, 11248, 112496, 1124992, 11249985, 112499976, 1124999972, 11249999992, 112500000074, 1125000000280, 11250000000692, 112500000001384}
NestList[Dot[NestList[RotateRight, {2, 1, 1, 1, 1, 1, 1, 2}, 7], #] &, {1, 2, 1, 1, 1, 1, 1, 1}, 14][[All, 1]]

(09)。数码和是9倍数的n位数。{1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000, 10000000000, 100000000000, 1000000000000, 10000000000000, 100000000000000}
NestList[Dot[NestList[RotateRight, {2, 1, 1, 1, 1, 1, 1, 1, 1}, 8], #] &, {1, 1, 1, 1, 1, 1, 1, 1, 1}, 14][[All, 1]]

(10)。数码和是10倍数的n位数。{0, 9, 90, 900, 9000, 90000, 900000, 9000000, 90000000, 900000000, 9000000000, 90000000000, 900000000000, 9000000000000, 90000000000000}
NestList[Dot[NestList[RotateRight, {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 9], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 14][[All, 1]]

(11)。数码和是11倍数的n位数。{0, 8, 82, 818, 8182, 81818, 818182, 8181818, 81818182, 818181818, 8181818181, 81818181819, 818181818182, 8181818181818, 81818181818182}
NestList[Dot[NestList[RotateRight, {1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 10], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0}, 14][[All, 1]]

(12)。数码和是12倍数的n位数。{0, 7, 76, 748, 7504, 74993, 749994, 7500059, 74999910, 750000001, 7500000200, 74999999501, 750000000944, 7499999999031, 74999999998090}
NestList[Dot[NestList[RotateRight, {1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 11], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0}, 14][[All, 1]]

(13)。数码和是13倍数的n位数。{0, 6, 72, 684, 6933, 69297, 692049, 6923265, 69231861, 692302884, 6923085159, 69230782122, 692307584595, 6923077148598, 69230769343458}
NestList[Dot[NestList[RotateRight, {1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 12], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0}, 14][[All, 1]]

(14)。数码和是14倍数的n位数。{0, 5, 70, 630, 6375, 64601, 642645, 6425599, 64297713, 642856767, 6428421494, 64286170240, 642857602231, 6428564424863, 64285730047092}
NestList[Dot[NestList[RotateRight, {1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 13], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0}, 14][[All, 1]]

(15)。数码和是15倍数的n位数。{0, 4, 69, 603, 5817, 60378, 602133, 5987904, 59994303, 600225342, 5999520723, 59997327243, 600015197949, 6000007240428, 59999717638617}
NestList[Dot[NestList[RotateRight, {1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 14], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0}, 14][[All, 1]]

(16)。数码和是16倍数的n位数。{0, 3, 66, 599, 5332, 55956, 569584, 5618444, 56103129, 562918205, 5627520744, 56235963162, 562469405642, 5625371327946, 56250000000692}
NestList[Dot[NestList[RotateRight, {1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 15], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0}, 14][[All, 1]]

(17)。数码和是17倍数的n位数。{0, 2, 61, 607, 5005, 51090, 539103, 5335482, 52635691, 528573446, 5303297495, 52955278635, 529146620809, 5293987371496, 52948567080626}
NestList[Dot[NestList[RotateRight, {1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1},16], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0}, 14][[All, 1]]

(18)。数码和是18倍数的n位数。{0, 1, 54, 616, 4884, 46300, 503700, 5118916, 49881084, 496175516, 5003824484, 50123007764, 499876992236, 4996043649836, 50003956350164}
NestList[Dot[NestList[RotateRight, {1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 17], #] &, {0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0}, 14][[All, 1]]

我们已经有18串数!第19串数还是出不来?
毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
 楼主| 发表于 2024-11-11 17:55:30 | 显示全部楼层
谢谢 mathe!谢谢 northwolves!第19串数是这样一串数。谢谢 mathe!谢谢 northwolves!

数码和是19倍数的n位数。
这样的1位数有0个。
这样的2位数有0个。
这样的3位数有45个。
这样的4位数有615个。
这样的5位数有4950个。
这样的6位数有42459个。

{0, 0, 45, 615, 4950, 42459, 461055, 4904064, 47998149, 468183583, 4708257444, 47541493289, 474905200991, 4731718185444, 47318535154702, 473822169622558, 4738808901078066, 47365330213246505,
473609016175792282, 4736880222305186899, 47371215824242761052, 473685607912121380526, 4736741045218682831468, 47368268763871963556939, 473687763138671735330650, 4736851240841544752628481,
47368299948038897783859250, 473683754507813934213227366, 4736846088986819720222655096, 47368441754173494253392923636, 473684085182976017895159800843, 4736841220993121292087042105101,  ......

这个矩阵特征多项式。用一个庞大的方程(19个=)才解出来的。往前冲一冲!若改成“71”, (71个=)。无法解了!
{x^19 - 19x^18 + 171x^17 - 1254x^16 + 6156x^15 - 22116x^14 + 60648x^13 - 130530x^12 + 224466x^11 - 311866x^10 + 352146x^9 - 323608x^8 + 241300x^7 - 144856x^6 + 69046x^5 - 25555x^4 + 7087x^3 - 1387x^2 + 171x - 10},
  1. Solve[{45 a + 615 b + 4950 c + 42459 d + 461055 f + 4904064 g + 47998149 h + 468183583 j + 4708257444 k + 47541493289 x + 474905200991 y + 4731718185444 z + 47318535154702 w +
  2.     473822169622558 s + 4738808901078066 t + 47365330213246505 u + 473609016175792282 v + 4736880222305186899 p + 47371215824242761052 q == 473685607912121380526,
  3. 615 a + 4950 b + 42459 c + 461055 d + 4904064 f + 47998149 g + 468183583 h + 4708257444 j + 47541493289 k + 474905200991 x + 4731718185444 y + 47318535154702 z + 473822169622558 w +
  4.     4738808901078066 s + 47365330213246505 t + 473609016175792282 u + 4736880222305186899 v + 47371215824242761052 p + 473685607912121380526 q == 4736741045218682831468,
  5. 4950 a + 42459 b + 461055 c + 4904064 d + 47998149 f + 468183583 g + 4708257444 h + 47541493289 j + 474905200991 k +
  6.     4731718185444 x + 47318535154702 y + 473822169622558 z + 4738808901078066 w + 47365330213246505 s + 473609016175792282 t +
  7.     4736880222305186899 u + 47371215824242761052 v + 473685607912121380526 p + 4736741045218682831468 q == 47368268763871963556939,
  8. 42459 a + 461055 b + 4904064 c + 47998149 d + 468183583 f + 4708257444 g + 47541493289 h + 474905200991 j + 4731718185444 k +
  9.     47318535154702 x + 473822169622558 y + 4738808901078066 z + 47365330213246505 w + 473609016175792282 s + 4736880222305186899 t +
  10.     47371215824242761052 u + 473685607912121380526 v + 4736741045218682831468 p + 47368268763871963556939 q == 473687763138671735330650,
  11. 461055 a + 4904064 b + 47998149 c + 468183583 d + 4708257444 f + 47541493289 g + 474905200991 h + 4731718185444 j + 47318535154702 k +
  12.     473822169622558 x + 4738808901078066 y + 47365330213246505 z + 473609016175792282 w + 4736880222305186899 s + 47371215824242761052 t +
  13.     473685607912121380526 u + 4736741045218682831468 v + 47368268763871963556939 p + 473687763138671735330650 q == 4736851240841544752628481,
  14. 4904064 a + 47998149 b + 468183583 c + 4708257444 d + 47541493289 f + 474905200991 g + 4731718185444 h + 47318535154702 j + 473822169622558 k +
  15.     4738808901078066 x + 47365330213246505 y + 473609016175792282 z + 4736880222305186899 w + 47371215824242761052 s + 473685607912121380526 t +
  16.     4736741045218682831468 u + 47368268763871963556939 v + 473687763138671735330650 p + 4736851240841544752628481 q == 47368299948038897783859250,
  17. 47998149 a + 468183583 b + 4708257444 c + 47541493289 d + 474905200991 f + 4731718185444 g + 47318535154702 h + 473822169622558 j + 4738808901078066 k +
  18.     47365330213246505 x + 473609016175792282 y + 4736880222305186899 z + 47371215824242761052 w + 473685607912121380526 s + 4736741045218682831468 t +
  19.     47368268763871963556939 u + 473687763138671735330650 v + 4736851240841544752628481 p + 47368299948038897783859250 q == 473683754507813934213227366,
  20. 468183583 a + 4708257444 b + 47541493289 c + 474905200991 d + 4731718185444 f + 47318535154702 g + 473822169622558 h + 4738808901078066 j + 47365330213246505 k +
  21.     473609016175792282 x + 4736880222305186899 y + 47371215824242761052 z + 473685607912121380526 w + 4736741045218682831468 s + 47368268763871963556939 t +
  22.     473687763138671735330650 u + 4736851240841544752628481 v + 47368299948038897783859250 p + 473683754507813934213227366 q == 4736846088986819720222655096,
  23. 4708257444 a + 47541493289 b + 474905200991 c + 4731718185444 d + 47318535154702 f + 473822169622558 g + 4738808901078066 h + 47365330213246505 j + 473609016175792282 k +
  24.     4736880222305186899 x + 47371215824242761052 y + 473685607912121380526 z + 4736741045218682831468 w + 47368268763871963556939 s + 473687763138671735330650 t +
  25.     4736851240841544752628481 u + 47368299948038897783859250 v + 473683754507813934213227366 p + 4736846088986819720222655096 q == 47368441754173494253392923636,
  26. 47541493289 a + 474905200991 b + 4731718185444 c + 47318535154702 d + 473822169622558 f + 4738808901078066 g + 47365330213246505 h + 473609016175792282 j + 4736880222305186899 k +
  27.     47371215824242761052 x + 473685607912121380526 y + 4736741045218682831468 z + 47368268763871963556939 w + 473687763138671735330650 s + 4736851240841544752628481 t +
  28.     47368299948038897783859250 u + 473683754507813934213227366 v + 4736846088986819720222655096 p + 47368441754173494253392923636 q == 473684085182976017895159800843,
  29. 474905200991 a + 4731718185444 b + 47318535154702 c + 473822169622558 d + 4738808901078066 f + 47365330213246505 g + 473609016175792282 h +
  30.     4736880222305186899 j + 47371215824242761052 k + 473685607912121380526 x + 4736741045218682831468 y + 47368268763871963556939 z +
  31.     473687763138671735330650 w + 4736851240841544752628481 s + 47368299948038897783859250 t + 473683754507813934213227366 u +
  32.     4736846088986819720222655096 v + 47368441754173494253392923636 p + 473684085182976017895159800843 q == 4736841220993121292087042105101,
  33. 4731718185444 a + 47318535154702 b + 473822169622558 c + 4738808901078066 d + 47365330213246505 f + 473609016175792282 g + 4736880222305186899 h +
  34.     47371215824242761052 j + 473685607912121380526 k + 4736741045218682831468 x + 47368268763871963556939 y + 473687763138671735330650 z +
  35.     4736851240841544752628481 w + 47368299948038897783859250 s + 473683754507813934213227366 t + 4736846088986819720222655096 u +
  36.     47368441754173494253392923636 v + 473684085182976017895159800843 p + 4736841220993121292087042105101 q == 47368424763497847253708298322323,
  37. 47318535154702 a + 473822169622558 b + 4738808901078066 c + 47365330213246505 d + 473609016175792282 f + 4736880222305186899 g + 47371215824242761052 h +
  38.     473685607912121380526 j + 4736741045218682831468 k + 47368268763871963556939 x + 473687763138671735330650 y + 4736851240841544752628481 z +
  39.     47368299948038897783859250 w + 473683754507813934213227366 s + 4736846088986819720222655096 t + 47368441754173494253392923636 u +
  40.     473684085182976017895159800843 v + 4736841220993121292087042105101 p + 47368424763497847253708298322323 q == 473684246654870591857254297499521,
  41. 473822169622558 a + 4738808901078066 b + 47365330213246505 c + 473609016175792282 d + 4736880222305186899 f + 47371215824242761052 g + 473685607912121380526 h +
  42.     4736741045218682831468 j + 47368268763871963556939 k + 473687763138671735330650 x + 4736851240841544752628481 y + 47368299948038897783859250 z +
  43.     473683754507813934213227366 w + 4736846088986819720222655096 s + 47368441754173494253392923636 t + 473684085182976017895159800843 u +
  44.     4736841220993121292087042105101 v + 47368424763497847253708298322323 p + 473684246654870591857254297499521 q == 4736842005349890744462129437152022,
  45. 4738808901078066 a + 47365330213246505 b + 473609016175792282 c + 4736880222305186899 d + 47371215824242761052 f + 473685607912121380526 g + 4736741045218682831468 h +
  46.     47368268763871963556939 j + 473687763138671735330650 k + 4736851240841544752628481 x + 47368299948038897783859250 y + 473683754507813934213227366 z +
  47.     4736846088986819720222655096 w + 47368441754173494253392923636 s + 473684085182976017895159800843 t + 4736841220993121292087042105101 u +
  48.     47368424763497847253708298322323 v + 473684246654870591857254297499521 p + 4736842005349890744462129437152022 q == 47368419628231233992493701524552869,
  49. 47365330213246505 a + 473609016175792282 b + 4736880222305186899 c + 47371215824242761052 d + 473685607912121380526 f + 4736741045218682831468 g + 47368268763871963556939 h +
  50.     473687763138671735330650 j + 4736851240841544752628481 k + 47368299948038897783859250 x + 473683754507813934213227366 y + 4736846088986819720222655096 z +
  51.     47368441754173494253392923636 w + 473684085182976017895159800843 s + 4736841220993121292087042105101 t + 47368424763497847253708298322323 u +
  52.     473684246654870591857254297499521 v + 4736842005349890744462129437152022 p + 47368419628231233992493701524552869 q == 473684212764775250719720677022308798,
  53. 473609016175792282 a + 4736880222305186899 b + 47371215824242761052 c + 473685607912121380526 d + 4736741045218682831468 f + 47368268763871963556939 g + 473687763138671735330650 h +
  54.     4736851240841544752628481 j + 47368299948038897783859250 k + 473683754507813934213227366 x + 4736846088986819720222655096 y + 47368441754173494253392923636 z +
  55.     473684085182976017895159800843 w + 4736841220993121292087042105101 s + 47368424763497847253708298322323 t + 473684246654870591857254297499521 u +
  56.     4736842005349890744462129437152022 v + 47368419628231233992493701524552869 p + 473684212764775250719720677022308798 q == 4736842159720696165874228312801395108,
  57. 4736880222305186899 a + 47371215824242761052 b + 473685607912121380526 c + 4736741045218682831468 d + 47368268763871963556939 f + 473687763138671735330650 g + 4736851240841544752628481 h +
  58.     47368299948038897783859250 j + 473683754507813934213227366 k + 4736846088986819720222655096 x + 47368441754173494253392923636 y + 473684085182976017895159800843 z +
  59.     4736841220993121292087042105101 w + 47368424763497847253708298322323 s + 473684246654870591857254297499521 t + 4736842005349890744462129437152022 u +
  60.     47368419628231233992493701524552869 v + 473684212764775250719720677022308798 p + 4736842159720696165874228312801395108 q == 47368421025026309923091387303805447925,
  61. 47371215824242761052 a + 473685607912121380526 b + 4736741045218682831468 c + 47368268763871963556939 d+473687763138671735330650 f+4736851240841544752628481 g+47368299948038897783859250 h +
  62.     473683754507813934213227366 j + 4736846088986819720222655096 k + 47368441754173494253392923636 x + 473684085182976017895159800843 y + 4736841220993121292087042105101 z +
  63.     47368424763497847253708298322323 w + 473684246654870591857254297499521 s + 4736842005349890744462129437152022 t + 47368419628231233992493701524552869 u +
  64.     473684212764775250719720677022308798 v + 4736842159720696165874228312801395108 p + 47368421025026309923091387303805447925 q == 473684208502275674834927080193549917674},
  65. {q, p, v, u, t, s, w, z, y, x, k, j, h, g, f, d, c, b, a}]
复制代码

q -> 19, p -> -171, v -> 1254, u -> -6156, t -> 22116, s -> -60648, w -> 130530, z -> -224466, y -> 311866, x -> -352146, k -> 323608, j -> -241300, h -> 144856, g -> -69046, f -> 25555, d -> -7087, c -> 1387, b -> -171, a -> 10}}

点评

这方程是电脑解的。这些数字可是一个一个一个一个输进去的。  发表于 2024-11-11 18:02
王老师很猛!  发表于 2024-11-11 17:57
毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
 楼主| 发表于 2024-11-12 15:23:10 | 显示全部楼层
  1. LinearRecurrence[{19, -171, 1254, -6156, 22116, -60648, 130530, -224466, 311866, -352146, 323608, -241300, 144856, -69046, 25555, -7087, 1387, -171, 10}, {0, 0, 45, 615, 4950, 42459,
  2. 461055, 4904064, 47998149, 468183583, 4708257444, 47541493289, 474905200991,4731718185444, 47318535154702, 473822169622558, 4738808901078066, 47365330213246505, 473609016175792282}, 32]
复制代码

{0, 0, 45, 615, 4950, 42459, 461055, 4904064, 47998149, 468183583, 4708257444, 47541493289, 474905200991, 4731718185444, 47318535154702, 473822169622558, 4738808901078066, 47365330213246505,
473609016175792282, 4736880222305186899, 47371215824242761052, 473685607912121380526, 4736741045218682831468, 47368268763871963556939, 473687763138671735330650, 4736851240841544752628481,
47368299948038897783859250, 473683754507813934213227366, 4736846088986819720222655096, 47368441754173494253392923636, 473684085182976017895159800843, 4736841220993121292087042105101,  ......
这样也可以。
  1. LinearRecurrence[{19, -171, 1254, -6156, 22116, -60648, 130530, -224466, 311866, -352146, 323608, -241300, 144856, -69046, 25555, -7087, 1387, -171, 10}, {13473684211/1000000000,
  2. 673684211/100000000, 33684211/10000000, 1684211/1000000, 84211/100000, 4211/10000, 211/1000, 11/100, 1/10, 0, 0, 45, 615, 4950, 42459, 461055, 4904064, 47998149, 468183583}, 41]
复制代码

{13473684211/1000000000, 673684211/100000000, 33684211/10000000, 1684211/1000000, 84211/100000, 4211/10000, 211/1000, 11/100, 1/10,
0, 0, 45, 615, 4950, 42459, 461055, 4904064, 47998149, 468183583, 4708257444, 47541493289, 474905200991, 4731718185444, 47318535154702, 473822169622558, 4738808901078066, 47365330213246505,
473609016175792282, 4736880222305186899, 47371215824242761052, \473685607912121380526, 4736741045218682831468, 47368268763871963556939, 473687763138671735330650, 4736851240841544752628481,
47368299948038897783859250, 473683754507813934213227366, 4736846088986819720222655096, 47368441754173494253392923636, 473684085182976017895159800843,4736841220993121292087042105101,  ......
毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
 楼主| 发表于 2024-11-12 15:24:11 | 显示全部楼层
接楼上。数字串(A)没有通项公式。数字串(B)还是可以有通项公式的。

数字串(A)。{0, 0, 45, 615, 4950, 42459, 461055, 4904064, 47998149, 468183583, 4708257444, 47541493289, 474905200991, 4731718185444, 47318535154702, 473822169622558, 4738808901078066, 47365330213246505,
473609016175792282, 4736880222305186899, 47371215824242761052, \473685607912121380526, 4736741045218682831468, 47368268763871963556939, 473687763138671735330650, 4736851240841544752628481,
47368299948038897783859250, 473683754507813934213227366, 4736846088986819720222655096, 47368441754173494253392923636, 473684085182976017895159800843,4736841220993121292087042105101,  ......

数字串(B)。{1, 11, 211, 4211, 84211, 1684211, 33684211, 673684211, 13473684211, 269473684211, 5389473684211, 107789473684211, 2155789473684211, 43115789473684211, 862315789473684211, 17246315789473684211,
344926315789473684211, 6898526315789473684211, 137970526315789473684211, 2759410526315789473684211, 55188210526315789473684211, 1103764210526315789473684211, 22075284210526315789473684211,
441505684210526315789473684211, 8830113684210526315789473684211, 176602273684210526315789473684211, 3532045473684210526315789473684211, 70640909473684210526315789473684211,  ......
  1. Table[Ceiling[20^n/38], {n, 39}]
复制代码
毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
 楼主| 发表于 2024-11-14 11:22:05 | 显示全部楼层
mathe 发表于 2024-11-7 13:41
这个矩阵特征多项式为\(x^7 - 14*x^6 + 49*x^5 - 98*x^4 + 84*x^3 - 42*x^2 + 21*x - 10\)
对应通向公式 ...

尊敬的mathe!虚心求教。

数码和是6倍数的n位数。

这样的1位数有1个。

这样的2位数有14个。

这样的3位数有151个。

这样的4位数有1503个。
......
{1, 14, 151, 1503, 14997, 149991, 1500009, 15000027, 149999973, 1499999919, 15000000081, 150000000243, 1499999999757, 14999999999271, 150000000000729}
  1. NestList[Dot[NestList[RotateRight, {2, 1, 1, 2, 2, 2}, 5], #] &, {1, 2, 2, 2, 1, 1}, 14][[All, 1]]
复制代码

这个矩阵可以有特征多项式吗?"有" 还是 "没有" 就可以。谢谢mathe!
毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
发表于 2024-11-14 11:52:58 | 显示全部楼层
$a(n)=10a(n-1)-3a(n-2)-30a(n-3)$
毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
 楼主| 发表于 2024-11-14 12:26:22 | 显示全部楼层
本帖最后由 王守恩 于 2024-11-14 17:56 编辑
northwolves 发表于 2024-11-14 11:52
$a(n)=10a(n-1)-3a(n-2)-30a(n-3)$

嗨!可以有的!特征多项式为x^3-10x^2+3x-30。
LinearRecurrence[{10, -3, 30}, {1, 14, 151, 1503}, 37]
{1, 14, 151, 1503, 14997, 149991, 1500009, 15000027, 149999973, 1499999919, 15000000081, 150000000243, 1499999999757, 14999999999271, 150000000000729, 1500000000002187,
LinearRecurrence[{10, -3, 30}, {7/6, 14, 151}, 37]
{7/6, 14, 151, 1503, 14997, 149991, 1500009, 15000027, 149999973, 1499999919, 15000000081, 150000000243, 1499999999757, 14999999999271, 150000000000729, 1500000000002187,
LinearRecurrence[{10, -3, 30}, {29/60, 7/6, 14}, 37]
{29/60, 7/6, 14, 151, 1503, 14997, 149991, 1500009, 15000027, 149999973, 1499999919, 15000000081, 150000000243, 1499999999757, 14999999999271, 150000000000729, 1500000000002187,
LinearRecurrence[{10, -3, 30}, {227/1800, 29/60, 7/6}, 37]
{227/1800, 29/60, 7/6, 14, 151, 1503, 14997, 149991, 1500009, 15000027, 149999973, 1499999919, 15000000081, 150000000243, 1499999999757, 14999999999271, 150000000000729, 1500000000002187,

毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
发表于 2024-11-14 15:54:30 | 显示全部楼层
$a_1=1,\ a_n=15*10^{n-1}+(-1)^n* 3^{\lfloor \frac{n-1}{2}\rfloor }$

点评

15*10^n - 3^Floor[n/2]*I^(n (n + 1))  发表于 2024-11-14 18:47
毋因群疑而阻独见  毋任己意而废人言
毋私小惠而伤大体  毋借公论以快私情
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