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A251871 Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 4 5 or 7 and every diagonal and antidiagonal sum 2 4 5 or 7 1

%I

%S 3092,7160,7080,9936,18464,31296,40816,93176,140408,223728,450520,

%T 814232,1178736,2773304,4759928,7729200,17426968,32932952,51615984,

%U 125418104,233934776,383184048,922678360,1780892312,2888662896,7132898744

%N Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum not 2 4 5 or 7 and every diagonal and antidiagonal sum 2 4 5 or 7

%C Column 3 of A251876

%H R. H. Hardin, <a href="/A251871/b251871.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 15*a(n-3) -50*a(n-6) -160*a(n-9) +1056*a(n-12) -1280*a(n-15) for n>22

%e Some solutions for n=4

%e ..2..0..1..2..0....1..3..2..1..3....1..0..2..1..0....2..0..1..2..0

%e ..3..3..3..0..3....0..1..2..0..1....0..1..2..3..1....2..2..2..2..2

%e ..1..0..2..1..3....2..2..2..2..2....2..2..2..2..2....2..1..3..2..1

%e ..2..3..1..2..0....1..3..2..1..3....1..0..2..1..3....2..0..1..2..0

%e ..0..0..0..3..3....0..1..2..0..1....0..1..2..0..1....2..2..2..2..2

%e ..1..3..2..1..3....2..2..2..2..2....2..2..2..2..2....2..1..0..2..1

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 10 2014

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Last modified May 27 14:37 EDT 2022. Contains 354105 sequences. (Running on oeis4.)