A172678 Number of 4*n X n 0..2 arrays with row sums 2 and column sums 8

1, 1107, 57775905, 40629560387130, 203571289613781911250, 4937928427617947420104982250, 447362835296127429187676764430583750, 125661678519106774927206307245894357500775000

Offset

1,2

Links

R. H. Hardin, Table of n, a(n) for n=1..24

Formula

a(n) = (1/(8!)^n)*Sum_(v=0..n} Sum_{m=0..n-v} Sum_{g=0..n-v-m} Sum_{b=0..n-v-m-g} (28^b*210^g*420^m*105^v*n!(4n)!(8n-2b-4g-6m-8v)!)/((n-b-g-m-v)!b!g!m!v!(4n-b-2g-3m-4v)!2^(4n-b-2g-3m-4v)). - Shanzhen Gao, Feb 25 2010

Crossrefs

Sequence in context: A172905 A172928 A172947 * A172774 A234156 A066163

Adjacent sequences: A172675 A172676 A172677 * A172679 A172680 A172681

Keyword

nonn

Author

R. H. Hardin, Feb 06 2010

Status

approved