A187632 - OEIS

%I #4 Mar 31 2012 12:36:09

%S 113,12104,106892,686589106,795758912

%N Number of (n+1)X(n+1) 0..4 arrays with the array of 2X2 subblock determinants antisymmetric under horizontal and vertical reflection and each non-centerline 2X2 subblock nonsingular

%C Column 4 of A187633

%e Some solutions for 4X4

%e ..3..1..3..0....0..4..4..4....0..4..3..2....0..2..4..0....1..4..4..4

%e ..3..0..0..1....1..0..0..1....3..0..0..4....2..0..0..1....1..0..0..1

%e ..1..0..0..3....2..0..0..1....4..0..0..3....1..0..0..2....4..0..0..1

%e ..3..3..1..0....1..2..4..0....2..3..4..2....2..4..2..0....4..1..4..3

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 12 2011