A377062 Number of inequivalent n X 4 nonnegative integer arrays with row sums 4 and column sums n up to permutations of rows and columns.
1, 1, 3, 9, 43, 147, 661, 2649, 10738, 40427, 146206, 498705, 1625621, 5049556, 15044485, 43044068, 118731621, 316347549, 816409799, 2044571309, 4979112445, 11810405775, 27331117859, 61792085482, 136670650003, 296071435108, 628900592847, 1311195696010, 2685731232674, 5409289235300, 10721363532282
Offset: 0
Keywords
Examples
The a(2) = 3 matrices are: [2 2 0 0] [2 1 1 0] [1 1 1 1] [0 0 2 2] [0 1 1 2] [1 1 1 1]