OFFSET
1,2
COMMENTS
See A368366 for further information.
LINKS
Paolo Xausa, Table of n, a(n) for n = 1..210
MATHEMATICA
A368369[n_] := With[{m = n^n}, m*(m-(2*n-1)!!)];
Array[A368369, 20] (* Paolo Xausa, Jan 29 2024 *)
PROG
(PARI) a368369(n) = {my(v=vector(n, i, i+i-1)); vecsum(v)^n - n^n*vecprod(v)}; \\ Hugo Pfoertner, Jan 24 2024
(Python)
from sympy import factorial2
def A368369(n): return (m:=n**n)*(m-factorial2((n<<1)-1)) # Chai Wah Wu, Jan 25 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jan 24 2024
STATUS
approved