OFFSET
0,4
PROG
(PARI) a(n) = my(A=1+O(x)); for(i=1, n, A=1+(n-i+1)*x^(n-i+1)/A); polcoef(A, n);
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Apr 16 2021
STATUS
approved