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A229415 Number of n X n 0..2 zero-diagonal arrays with corresponding row and column sums equal.

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%I A229415 #7 Jul 23 2025 05:43:52
%S A229415 1,3,45,4743,3801411,23938685973,1215663478473627
%N A229415 Number of n X n 0..2 zero-diagonal arrays with corresponding row and column sums equal.
%C A229415 Column 2 of A229417
%e A229415 Some solutions for n=4
%e A229415 ..0..1..2..1....0..1..2..0....0..0..2..0....0..1..1..2....0..2..0..1
%e A229415 ..2..0..2..0....2..0..0..0....2..0..1..0....0..0..2..0....2..0..0..1
%e A229415 ..0..2..0..2....0..1..0..1....0..2..0..1....2..1..0..2....0..1..0..0
%e A229415 ..2..1..0..0....1..0..0..0....0..1..0..0....2..0..2..0....1..0..1..0
%K A229415 nonn
%O A229415 1,2
%A A229415 _R. H. Hardin_ Sep 22 2013

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