OFFSET
0,2
LINKS
Winston de Greef, Table of n, a(n) for n = 0..1139
FORMULA
a(n) = Sum_{k=0..n} binomial(2*k,k) * binomial(5*k,n-k).
n*a(n) = 2 * ( (2*n-1)*a(n-1) + 5*(2*n-2)*a(n-2) + 10*(2*n-3)*a(n-3) + 10*(2*n-4)*a(n-4) + 5*(2*n-5)*a(n-5) + (2*n-6)*a(n-6) ) for n > 5.
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(1/sqrt(1-4*x*(1+x)^5))
(PARI) a(n)= sum(k=0, n, binomial(2*k, k) * binomial(5*k, n-k)) \\ Winston de Greef, Mar 25 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Mar 25 2023
STATUS
approved