A331637 Number of binary matrices with nonzero rows, a total of n ones and each column with the same number of ones.

1, 4, 14, 89, 542, 5156, 47294, 570074, 7103343, 104493608, 1622632574, 28411638982, 526858348382, 10699857854372, 230297862127828, 5330284144906443, 130370767029135902, 3390229775073259800, 92801587319328411134, 2679531116538955252338

Offset: 1

Author

Andrew Howroyd, Jan 23 2020

Keywords

• nonn

Examples

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

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..200

Crossrefs

Cf. A262809.

Formula

a(n) = Sum_{d|n} A262809(n/d, d).