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A252533 Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 3 6 or 7.

%I A252533 #6 Jun 02 2025 11:20:13
%S A252533 750,730,621,719,778,932,1200,1498,1968,2708,3473,4698,6444,8494,
%T A252533 11435,15560,20630,27462,36761,48910,64407,85224,113390,148048,193940,
%U A252533 258080,334681,435134,578923,746716,964795,1283490,1648229,2118894,2818420
%N A252533 Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 3 6 or 7.
%C A252533 Row 1 of A252532
%H A252533 R. H. Hardin, <a href="/A252533/b252533.txt">Table of n, a(n) for n = 1..210</a>
%F A252533 Empirical: a(n) = 4*a(n-3) -3*a(n-6) -4*a(n-9) +4*a(n-12) for n>39
%e A252533 Some solutions for n=4
%e A252533 ..2..2..2..3..1..3....3..1..3..3..1..3....3..3..0..0..0..3....1..1..0..1..1..0
%e A252533 ..2..1..0..1..1..0....2..2..3..2..2..3....3..2..2..3..1..3....3..0..0..3..0..3
%e A252533 ..1..2..3..1..3..2....3..2..2..3..1..2....2..3..2..1..3..2....1..0..1..1..0..1
%K A252533 nonn
%O A252533 1,1
%A A252533 _R. H. Hardin_, Dec 18 2014