OFFSET
0,2
COMMENTS
Self-convolution of A118803.
PROG
(PARI) {a(n)=sum(k=0, n, (1+(-1)^k*2^(n-k+1)*sum(j=0, k\2, binomial(n-2*j-2, k-2*j-1)))^2)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, May 02 2006
STATUS
approved