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%I #6 Apr 17 2022 23:01:47
%S 64,130,295,687,1591,3650,8389,19412,45002,104255,241737,561451,
%T 1305496,3038129,7076836,16500354,38507303,89941465,210246081,
%U 491853090,1151508703,2697778070,6324654030,14836947029,34826937451,81796528951
%N Number of (n+2) X (1+2) 0..2 arrays with every 3 X 3 subblock row, column, diagonal and antidiagonal sum not equal to 1 3 or 4.
%C Column 1 of A252088.
%H R. H. Hardin, <a href="/A252081/b252081.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) -3*a(n-2) +9*a(n-3) -9*a(n-4) +4*a(n-5) -22*a(n-6) -14*a(n-7) -19*a(n-8) -8*a(n-9) +8*a(n-10) +18*a(n-11) +24*a(n-12) +20*a(n-13) +6*a(n-14) -4*a(n-15) -8*a(n-16) -4*a(n-17) for n>18.
%e Some solutions for n=4
%e ..2..1..2....2..1..2....2..0..0....2..2..2....2..0..0....0..2..0....0..0..0
%e ..2..2..1....2..2..2....0..0..0....0..0..0....0..2..0....2..0..0....0..2..0
%e ..2..2..2....2..2..2....0..2..0....0..0..0....0..0..2....0..0..2....0..0..0
%e ..2..2..2....1..2..2....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
%e ..2..2..2....2..2..2....0..0..0....0..0..0....0..0..0....0..0..0....0..2..0
%e ..2..2..1....2..2..2....2..0..0....0..0..2....2..0..0....0..0..0....0..0..0
%Y Cf. A252088.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 13 2014
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