OFFSET
0,3
FORMULA
a(0) = 1, a(1) = 0, a(2) = 14; a(n) = (4*(n+5)*a(n-2) + 2*(2*n+15)*a(n-3))/n.
a(n) = Sum_{k=0..floor(n/2)} (-4)^k * binomial(-7/2,k) * binomial(k,n-2*k).
PROG
(PARI) a(n) = sum(k=0, n\2, (-4)^k*binomial(-7/2, k)*binomial(k, n-2*k));
CROSSREFS
KEYWORD
nonn,new
AUTHOR
Seiichi Manyama, Oct 19 2024
STATUS
approved