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Number of n X n binary matrices with rows and columns each in strictly increasing order as binary numbers and every 0 adjacent to a 1 and every 1 adjacent to a 0
0

%I #3 Dec 18 2015 18:17:26

%S 0,1,1,1,2,8,59,744,19644,1150827,158171825,54785832985,50665615156541

%N Number of n X n binary matrices with rows and columns each in strictly increasing order as binary numbers and every 0 adjacent to a 1 and every 1 adjacent to a 0

%C Diagonal of A181011

%e All solutions for 6X6

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

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

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

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

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

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

%e ...

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

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

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

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

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

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

%K nonn

%O 1,5

%A _R. H. Hardin_ Sep 30 2010