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

1,2

Links

Table of n, a(n) for n=1..20.

Formula

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

Example

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

Crossrefs

Cf. A262809.

Sequence in context: A352289 A330465 A202139 * A340024 A190481 A316414

Adjacent sequences: A331634 A331635 A331636 * A331638 A331639 A331640

Keyword

nonn

Author

Andrew Howroyd, Jan 23 2020

Status

approved