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A187521 T(n,k)=Number of (n+1)X(n+1) 0..k arrays with the array of 2X2 subblock determinants antisymmetric and no off-diagonal 2X2 subblock determinant zero.

%I A187521 #7 Jul 22 2025 10:47:49
%S A187521 10,31,6,64,98,2,113,450,354,0,170,1590,4200,1780,0,255,3426,34776,
%T A187521 73764,12008,0,336,8546,107990,1655170,2048596,157694,0,449,13992,
%U A187521 475370,8174314,144075566,129034386,2808560,0,570,26158,978568,70304076
%N A187521 T(n,k)=Number of (n+1)X(n+1) 0..k arrays with the array of 2X2 subblock determinants antisymmetric and no off-diagonal 2X2 subblock determinant zero.
%C A187521 Table starts
%C A187521 .10......31........64.......113........170......255....336...449.570
%C A187521 ..6......98.......450......1590.......3426.....8546..13992.26158
%C A187521 ..2.....354......4200.....34776.....107990...475370.978568
%C A187521 ..0....1780.....73764...1655170....8174314.70304076
%C A187521 ..0...12008...2048596.144075566.1201064094
%C A187521 ..0..157694.129034386
%C A187521 ..0.2808560
%C A187521 ..0
%H A187521 R. H. Hardin, <a href="/A187521/b187521.txt">Table of n, a(n) for n = 1..41</a>
%e A187521 Some k=3 solutions for 5X5
%e A187521 ..0..0..2..0..2....2..3..2..1..1....2..1..2..3..3....1..1..0..3..1
%e A187521 ..2..1..1..2..0....2..3..3..3..2....2..1..1..1..2....1..1..1..0..2
%e A187521 ..2..2..2..2..1....3..3..3..1..2....1..1..1..2..1....2..1..1..1..2
%e A187521 ..2..0..1..1..1....2..1..3..1..1....1..2..1..2..2....1..2..1..1..1
%e A187521 ..0..2..3..2..2....3..2..2..1..1....2..1..2..2..2....3..0..1..2..2
%Y A187521 Row 1 is A059306
%K A187521 nonn,tabl
%O A187521 1,1
%A A187521 _R. H. Hardin_ Mar 10 2011