OFFSET
0,3
FORMULA
G.f. A(x) satisfies:
(1) A(x)^2 = 1 + x * A(x) * (1 + A(x)^5).
(2) A(x) = sqrt(B(x)) where B(x) is the g.f. of A370471.
a(n) = Sum_{k=0..n} binomial(n,k) * binomial(n/2+5*k/2+1/2,n)/(n+5*k+1).
PROG
(PARI) a(n) = sum(k=0, n, binomial(n, k)*binomial(n/2+5*k/2+1/2, n)/(n+5*k+1));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Mar 31 2024
STATUS
approved