简单的高秩曲线
无意间 留意到一篇论文, http://dx.doi.org/10.1155/S0161171200002210有一族曲线, $y^2=x^3-t^2x+1$,看似简单, 却有大量的高秩.
$1<t<1000$的统计情况如下, 秩为7的竟然有9个,分别是$ t = 347,443,614,757,778,784,857,877,888$
1 1
2 2
3 220
4 413
5 272
6 82
7 9
(20252716.12:27:03)> E=ellinit([-347^2,1])
%29 = ), )], ]
(20254316.23:43:03)> ellrank(E,1)
%30 = , [-345, 691], [-181, 3983], [-163, 3911], [-105, 3389], [-77, 2969], ]]
(20254316.23:43:11)> E=ellinit([-888^2,1])
%31 = ), )], ]
(20254316.23:43:29)> ellrank(E,1)
%32 = , [-820, 9759], [-705, 14336], [-228, 12959], [-76, 7713], [-1, 888], ]] 秩是生成元个数，还是元素个数？
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