OFFSET
0,3
FORMULA
a(n) = Sum_{k=0..floor((n-1)/2)} n^(n-1-k) * binomial(n,2*k+1).
a(n) = [x^n] x/(1 - 2*n*x + (n-1)*n*x^2).
a(n) = n! * [x^n] exp(n * x) * sinh(sqrt(n) * x) / sqrt(n) for n > 0.
PROG
(PARI) a(n) = polcoeff(lift(Mod('x, ('x-n)^2-n)^n), 1); \\ Kevin Ryde, Mar 16 2023
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Seiichi Manyama, Mar 11 2023
STATUS
approved