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A187633 T(n,k)=Number of (n+1)X(n+1) 0..k arrays with the array of 2X2 subblock determinants antisymmetric under horizontal and vertical reflection and each non-centerline 2X2 subblock nonsingular.

%I A187633 #6 Jul 22 2025 10:51:19
%S A187633 10,31,24,64,446,24,113,2924,1648,954,170,12104,14044,557382,954,255,
%T A187633 37448,106892,31903442,672698,194008,336,98014,306320,686589106,
%U A187633 33869160,21411605018,194008,449,221640,1848504,7836968262,795758912
%N A187633 T(n,k)=Number of (n+1)X(n+1) 0..k arrays with the array of 2X2 subblock determinants antisymmetric under horizontal and vertical reflection and each non-centerline 2X2 subblock nonsingular.
%C A187633 Table starts
%C A187633 .....10..........31.......64.......113........170.....255....336.449
%C A187633 .....24.........446.....2924.....12104......37448...98014.221640
%C A187633 .....24........1648....14044....106892.....306320.1848504
%C A187633 ....954......557382.31903442.686589106.7836968262
%C A187633 ....954......672698.33869160.795758912
%C A187633 .194008.21411605018
%C A187633 .194008
%e A187633 Some k=3 solutions for 5X5
%e A187633 ..2..0..2..1..2....2..0..2..0..2....2..0..2..1..2....2..0..2..1..3
%e A187633 ..0..1..0..1..0....0..3..2..3..0....0..2..0..2..0....0..3..0..3..3
%e A187633 ..3..1..3..1..3....2..0..2..0..2....2..1..2..0..2....2..0..2..0..2
%e A187633 ..0..1..0..1..0....0..3..0..3..0....0..2..0..2..2....1..3..0..3..3
%e A187633 ..2..2..2..1..2....2..3..2..0..2....2..2..2..0..2....3..3..2..1..3
%Y A187633 Row 1 is A059306
%Y A187633 Row 2 is A187625
%K A187633 nonn,tabl
%O A187633 1,1
%A A187633 _R. H. Hardin_ Mar 12 2011