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Number of n X n binary arrays with row sums nondecreasing and columns lexicographically nondecreasing.
0

%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