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%I #4 Dec 29 2015 10:20:02
%S 8,70,826,12758,223075,3825307,59155748,798834778,9379683461,
%T 96481143688,879275711012,7183343579974,53182973236784,
%U 360298764101463,2252503422916387,13090825673375302,71176326297105679,364068218093477268
%N Number of 7Xn binary arrays with rows and columns lexicographically nondecreasing and column sums nondecreasing.
%C Row 7 of A266428.
%H R. H. Hardin, <a href="/A266433/b266433.txt">Table of n, a(n) for n = 1..210</a>
%H R. H. Hardin, <a href="/A266433/a266433.txt">Empirical polynomial of degree 57</a>
%F Empirical polynomial of degree 57 (see link above)
%e Some solutions for n=4
%e ..0..0..0..0....0..0..0..0....0..0..1..1....0..0..0..0....0..0..0..1
%e ..0..0..1..1....0..0..0..0....0..1..0..1....0..0..1..1....0..0..0..1
%e ..0..0..1..1....0..0..0..1....0..1..1..0....0..0..1..1....0..0..0..1
%e ..0..1..0..1....0..0..0..1....0..1..1..1....0..1..0..0....0..1..1..0
%e ..0..1..0..1....0..0..0..1....1..0..0..0....0..1..0..1....0..1..1..0
%e ..1..0..1..1....0..1..1..0....1..0..1..0....0..1..0..1....1..0..0..1
%e ..1..1..0..0....0..1..1..0....1..1..0..1....1..0..1..0....1..0..1..1
%Y Cf. A266428.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 29 2015