A369027 a(n) = floor(n^2 * (n - 1)^(n - 1) / 2).

0, 0, 2, 18, 216, 3200, 56250, 1143072, 26353376, 679477248, 19371024450, 605000000000, 20542440283992, 753410487877632, 29681760446040794, 1250100767875276800, 56050417968750000000, 2665554518651030208512, 134012922425586555796674

Offset

0,3

Links

Table of n, a(n) for n=0..18.

Mathematica

A369027[n_] := If[n == 1, 0, n^2 (n-1)^(n-1) / 2];
Array[A369027, 30, 0] (* Paolo Xausa, Jan 12 2024 *)

Prog

(SageMath)
def A369027(n): return ((n - 1)^(n - 1)*n^2)//2
print([A369027(n) for n in range(22)])

Crossrefs

Cf. A369025, A369026.

Sequence in context: A092882 A123855 A121407 * A153647 A052726 A217239

Adjacent sequences: A369024 A369025 A369026 * A369028 A369029 A369030

Keyword

nonn

Author

Peter Luschny, Jan 12 2024

Status

approved