OFFSET
0,2
LINKS
Nathaniel Johnston, Table of n, a(n) for n = 0..75
FORMULA
a(n) = Sum_{k=0..2*n} binomial(k*(k+1)/2+n-1, n)*(Sum_{r=k..2*n} binomial(r, k)*(-1)^(r-k)). - Andrew Howroyd, Sep 15 2018
MAPLE
seq(sum(binomial(m*(m+1)/2+n-1, n)/2^(m+1), m=0..infinity), n=0..10);
PROG
(PARI) a(n)={sum(k=0, 2*n, binomial(k*(k+1)/2+n-1, n)*sum(r=k, 2*n, binomial(r, k)*(-1)^(r-k)) )} \\ Andrew Howroyd, Sep 15 2018
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Sep 06 2006
STATUS
approved