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%I #4 Oct 28 2015 11:46:25
%S 2,2,7,7,61,379,62904,16701495
%N Number of (n+1)X(n+1) 0..1 arrays with each row and column divisible by 3, read as a binary number with top and left being the most significant bits, and rows and columns lexicographically nondecreasing.
%C Diagonal of A263873.
%e Some solutions for n=4
%e ..0..0..0..0..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
%e ..0..1..1..1..1....0..0..0..1..1....0..0..0..0..0....0..0..0..1..1
%e ..0..1..1..1..1....0..0..0..1..1....0..0..0..0..0....0..0..0..1..1
%e ..0..1..1..1..1....0..1..1..1..1....0..0..0..1..1....0..0..0..1..1
%e ..0..1..1..1..1....0..1..1..1..1....0..0..0..1..1....0..0..0..1..1
%Y Cf. A263873.
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 28 2015
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