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%I #4 Oct 26 2015 13:36:46
%S 5,5,25,56,494,4991,62904,760671,8468941,90476206,850301770,
%T 7703098612,62160939006,482749236704,3416830587073,23238401292501,
%U 146883022822593,892090634118666,5108443008090443,28144017611172958,147708619212786406
%N Number of (n+1)X(7+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 nonincreasing
%C Column 7 of A263799
%H R. H. Hardin, <a href="/A263798/b263798.txt">Table of n, a(n) for n = 1..76</a>
%e Some solutions for n=5
%e ..1..1..1..1..0..0..0..0....1..1..1..1..0..0..0..0....1..1..1..1..1..1..0..0
%e ..1..1..0..0..1..1..0..0....1..1..0..0..1..1..0..0....1..1..1..1..0..0..1..1
%e ..1..0..1..0..1..1..1..0....1..0..1..0..1..0..1..1....1..1..0..0..1..1..1..1
%e ..1..0..0..1..0..0..0..0....1..0..0..1..0..0..1..1....1..1..0..0..0..0..0..0
%e ..0..1..1..0..1..0..0..1....0..0..1..0..0..1..1..1....0..0..0..0..1..1..1..1
%e ..0..1..0..0..1..0..1..1....0..0..0..0..0..0..1..1....0..0..0..0..0..0..1..1
%Y Cf. A263799
%K nonn
%O 1,1
%A _R. H. Hardin_, Oct 26 2015