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%I #6 Jan 20 2024 16:41:25
%S 113,31461,1718,875696,4612
%N Number of (n+1) X (n+1) 0..4 arrays with each 2 X 2 subblock off diagonal and antidiagonal nonsingular and the array of 2 X 2 subblock determinants antisymmetric about the diagonal and antidiagonal.
%C Column 4 of A187705.
%e Some solutions for 4 X 4
%e ..0..2..1..1....0..0..1..0....2..2..4..2....0..3..0..0....4..3..4..4
%e ..0..1..1..1....3..2..1..0....2..2..2..1....0..1..1..2....4..3..3..3
%e ..1..1..1..0....2..2..1..2....2..4..4..4....3..3..3..3....3..3..3..4
%e ..3..3..4..0....4..4..1..2....2..4..3..3....0..0..1..1....1..1..0..0
%Y Cf. A187705.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 12 2011
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