2,2

a(m,n)=2^{-m}\sum_{i=0}^{n}frac{(-1)^{i}m!n!(2m-2i)!}{i!(m-i)!(n-i)!6^{n-i}% }$

Sequence in context: A120809 A022062 A107526 this_sequence A134647 A054815 A023744

Adjacent sequences: A132199 A132200 A132201 this_sequence A132203 A132204 A132205

nonn

Shanzhen Gao (sgao2(AT)fau.edu), Nov 05 2007

Perhaps "Number of n+1 X n (0,1)-matrices ..." ? - njas