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A331637 Number of binary matrices with nonzero rows, a total of n ones and each column with the same number of ones. 1

%I

%S 1,4,14,89,542,5156,47294,570074,7103343,104493608,1622632574,

%T 28411638982,526858348382,10699857854372,230297862127828,

%U 5330284144906443,130370767029135902,3390229775073259800,92801587319328411134,2679531116538955252338

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

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

%e The a(2) = 4 matrices are:

%e [1] [1 0] [0 1] [1 1]

%e [1] [0 1] [1 0]

%Y Cf. A262809.

%K nonn

%O 1,2

%A _Andrew Howroyd_, Jan 23 2020

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Last modified May 23 16:11 EDT 2022. Contains 353976 sequences. (Running on oeis4.)