OFFSET
0,2
COMMENTS
FORMULA
a(n) = binomial(n+5, 2)*binomial(2*(n+3), n+2)/6 - (n+3)*2^(2*n+3); G.f. c(x)^2/(1-4*x)^(5/2), where c(x) = g.f. for Catalan numbers A000108;
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
STATUS
approved