A331721 Number of nonequivalent n-column nonnegative integer matrices with column sums 4 and any number of nonzero rows up to permutation of rows and columns.

1, 5, 66, 1338, 43686, 2142277, 149056260, 13991691663, 1705750869937, 262268740077763, 49694977078927305, 11388565848749818055, 3107918736854019004136, 996840601151518793573156, 371595543159269706775806375, 159437222426663041455988930042, 78072200940916732097886063687252

Offset: 0

Author

Andrew Howroyd, Jan 31 2020

Keywords

• nonn

Crossrefs

Row n=4 of A331485.