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%I #6 Apr 20 2020 19:44:48
%S 2,7,42,567,20040,2093467,683027146,723576702570,2549735632656528,
%T 30465608408449993885,1250919952257037350168062,
%U 178764247753852768666003981113,89752660973687899647122735126286078
%N Number of n X n binary arrays with row sums nondecreasing and columns lexicographically nondecreasing.
%C Diagonal of A267245.
%e Some solutions for n=4
%e ..0..0..0..1....0..0..0..1....0..0..1..1....0..0..0..1....0..0..0..1
%e ..0..1..1..0....0..0..0..1....0..1..0..1....0..0..1..1....0..0..1..1
%e ..1..0..1..0....0..0..1..1....1..1..0..0....0..1..0..1....1..1..1..0
%e ..1..1..1..1....1..1..1..0....1..1..0..0....1..1..1..0....1..1..0..1
%Y Cf. A267245.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 12 2016
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