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A252531 Number of (n+2) X (7+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 2 3 6 or 7.

%I A252531 #8 Dec 04 2018 11:04:15
%S A252531 1200,1468,2404,3160,11456,19232,25280,91648,153856,202240,733184,
%T A252531 1230848,1617920,5865472,9846784,12943360,46923776,78774272,103546880,
%U A252531 375390208,630194176,828375040,3003121664,5041553408,6627000320
%N A252531 Number of (n+2) X (7+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 0 2 3 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 0 2 3 6 or 7.
%H A252531 R. H. Hardin, <a href="/A252531/b252531.txt">Table of n, a(n) for n = 1..210</a>
%F A252531 Empirical: a(n) = 8*a(n-3) for n>5.
%F A252531 Empirical g.f.: 4*x*(300 + 367*x + 601*x^2 - 1610*x^3 - 72*x^4) / ((1 - 2*x)*(1 + 2*x + 4*x^2)). - _Colin Barker_, Dec 04 2018
%e A252531 Some solutions for n=4:
%e A252531 ..3..2..2..3..2..2..3..2..2....1..1..0..1..1..0..1..1..0
%e A252531 ..3..1..3..3..1..3..3..1..3....0..1..1..0..1..1..0..1..1
%e A252531 ..2..2..3..2..2..3..2..2..3....0..3..0..0..3..0..0..3..0
%e A252531 ..3..2..2..3..2..2..3..2..2....1..1..0..1..1..0..1..1..0
%e A252531 ..3..0..3..3..1..3..3..0..3....0..1..1..0..1..1..0..1..1
%e A252531 ..2..2..3..2..2..3..2..2..3....3..3..0..0..2..0..0..2..0
%Y A252531 Column 7 of A252532.
%K A252531 nonn
%O A252531 1,1
%A A252531 _R. H. Hardin_, Dec 18 2014