组合数累积求和
\(\displaystyle \sum_{k=0}^{n-2}\dbinom n k \dbinom n { k+1}\dbinom n {k +2}=?\) 1/2 (-1 + n) n^2 HypergeometricPFQ[{1 - n, 2 - n, -n}, {2, 3}, -1] wayne 发表于 2024-3-25 19:091/2 (-1 + n) n^2 HypergeometricPFQ[{1 - n, 2 - n, -n}, {2, 3}, -1]
机算得出的吗？ ShuXueZhenMiHu 发表于 2024-3-26 09:42
我期待的不是雪……
页:
[1]