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A252070 Number of (n+2)X(3+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 or 4.

%I A252070 #6 Jun 02 2025 10:45:26
%S A252070 183,419,1497,5085,17455,60245,206747,711749,2455039,8451165,29078125,
%T A252070 100127009,344830169,1187280673,4087598979,14073866379,48459148697,
%U A252070 166851565147,574482172193,1977991833479,6810453196661,23449166058617
%N A252070 Number of (n+2)X(3+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 or 4.
%C A252070 Column 3 of A252075
%H A252070 R. H. Hardin, <a href="/A252070/b252070.txt">Table of n, a(n) for n = 1..210</a>
%F A252070 Empirical: a(n) = 2*a(n-1) +11*a(n-3) +20*a(n-4) +12*a(n-5) -7*a(n-6) -69*a(n-7) -49*a(n-8) +69*a(n-9) +59*a(n-10) -9*a(n-11) -30*a(n-12) -14*a(n-13) +2*a(n-14) +4*a(n-16) for n>18
%e A252070 Some solutions for n=4
%e A252070 ..2..2..2..2..2....2..1..2..2..2....2..2..2..2..2....2..2..2..2..1
%e A252070 ..2..2..2..2..2....1..2..2..2..2....2..2..2..2..2....2..2..2..2..2
%e A252070 ..2..2..2..2..2....2..2..2..2..1....2..2..2..2..1....2..2..2..2..2
%e A252070 ..2..2..2..2..1....2..2..2..2..2....2..2..2..2..2....1..2..2..2..2
%e A252070 ..2..1..2..2..2....2..1..2..2..2....2..1..2..2..2....2..2..2..2..1
%e A252070 ..2..2..2..1..2....2..2..2..2..2....2..2..2..2..1....2..2..2..1..2
%K A252070 nonn
%O A252070 1,1
%A A252070 _R. H. Hardin_, Dec 13 2014