A204733 - OEIS

A204733

Number of (n+1) X (n+1) 0..1 arrays with rows and columns of permanents of all 2 X 2 subblocks lexicographically nondecreasing, and all 2 X 2 permanents nonzero.

%I #8 Oct 01 2021 18:30:06

%S 7,43,409,6176,150132,5920734,384523522,42202897239,8122473947642,

%T 2916065637047374

%N Number of (n+1) X (n+1) 0..1 arrays with rows and columns of permanents of all 2 X 2 subblocks lexicographically nondecreasing, and all 2 X 2 permanents nonzero.

%C Diagonal of A204740.

%e Some solutions for n=4

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

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

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

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

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

%Y Cf. A204740.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 18 2012