OFFSET
0,3
FORMULA
See A385063.
PROG
(PARI) a(n, k=-1) = if(n*k==0, 0^n, (-1)^n*k*sum(j=1, n, (-n+k)^(j-1)*binomial(n, j)*a(n-j, 3*j)));
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Jun 16 2025
STATUS
approved
