OFFSET
0,2
FORMULA
a(0) = 1, a(1) = 10, a(2) = 90; a(n) = (2*(2*n+3)*a(n-1) + 8*(n+3)*a(n-2) + 2*(2*n+9)*a(n-3))/n.
a(n) = Sum_{k=0..n} (-4)^k * binomial(-5/2,k) * binomial(2*k,n-k).
PROG
(PARI) a(n) = sum(k=0, n, (-4)^k*binomial(-5/2, k)*binomial(2*k, n-k));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 19 2024
STATUS
approved