A266469 - OEIS

%I #3 Dec 29 2015 19:55:46

%S 2,9,52,463,5371,77320,1231170,20115063,319006954,4768598707,

%T 66353854322,856330630443,10262183989448

%N Number of nX7 binary arrays with rows and columns lexicographically nondecreasing and column sums nonincreasing.

%C Column 7 of A266470.

%e Some solutions for n=4

%e ..0..0..0..0..0..0..0....0..0..0..1..1..1..1....0..0..0..0..0..0..0

%e ..0..0..0..0..0..0..0....0..1..1..0..0..0..0....0..0..0..0..0..0..1

%e ..0..0..0..0..0..0..1....1..0..0..1..1..1..1....0..0..0..1..1..1..0

%e ..1..1..1..1..1..1..0....1..1..1..0..0..0..0....1..1..1..0..0..0..0

%Y Cf. A266470.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 29 2015