OFFSET
0,3
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..81
FORMULA
PROG
(PARI) a(n) = my(A=1+O(x)); for(i=1, n, A=1+2^(n-i)*x/A); polcoef(A, n);
(PARI) a(n) = if(n<2, 1, -sum(k=1, n-1, 2^k*a(k)*a(n-k)));
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Apr 15 2021
STATUS
approved