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A331636 Number of nonnegative integer matrices with nonzero rows, total sum n and columns with equal sums. 1

%I #7 Jan 24 2020 06:09:25

%S 1,5,17,109,557,5785,47357,596365,7151841,106763725,1622633597,

%T 28757539337,526858352477,10758375762109,230342261913169,

%U 5344946955452877,130370767029201437,3394996816992588345,92801587319328673277,2681375183085608280093

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

%F a(n) = Sum_{d|n} A316674(n/d, d).

%e The a(2) = 5 matrices are:

%e [1] [1 0] [0 1] [2] [1 1]

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

%Y Cf. A316674.

%K nonn

%O 1,2

%A _Andrew Howroyd_, Jan 23 2020

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Last modified April 20 04:51 EDT 2024. Contains 371798 sequences. (Running on oeis4.)