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A252426 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 4 6 or 7 1

%I

%S 641,602,608,878,1152,1603,2617,4131,6514,11116,18318,29859,51493,

%T 85589,140525,243028,404779,665504,1151754,1919298,3156379,5463943,

%U 9106163,14976103,25929380,43214599,71070066,123069528,205112198,337314463

%N Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 4 6 or 7

%C Column 1 of A252433

%H R. H. Hardin, <a href="/A252426/b252426.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 11*a(n-3) -39*a(n-6) +57*a(n-9) -72*a(n-12) +60*a(n-15) -31*a(n-18) +17*a(n-21) -a(n-24) -a(n-27) for n>34

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 17 2014

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Last modified August 14 12:13 EDT 2020. Contains 336480 sequences. (Running on oeis4.)