A331648 Number of nonnegative integer matrices with distinct nonzero rows, total sum n and columns with equal sums.

1, 4, 16, 91, 546, 5094, 47306, 561190, 7098943, 103345704, 1622632638, 28216141886, 526858348514, 10659286804538, 230286817182060, 5319206290975993, 130370767029136518, 3386434807625742926, 92801587319328412310, 2677967917777310591454, 81124837170900250181072

Offset

1,2

Links

Table of n, a(n) for n=1..21.

Formula

a(n) = Sum_{d|n} A331568(d/n, d).

Example

The a(2) = 4 matrices are:
   [1 0]  [0 1]  [1 1]  [2]
   [0 1]  [1 0]

Crossrefs

Cf. A331568.

Sequence in context: A124962 A292088 A221818 * A009568 A139155 A003762

Adjacent sequences: A331645 A331646 A331647 * A331649 A331650 A331651

Keyword

nonn

Author

Andrew Howroyd, Jan 24 2020

Status

approved