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%I #4 Dec 17 2014 09:57:58
%S 293,442,774,1157,2489,5060,8307,19629,41216,69493,168252,355926,
%T 607953,1485818,3150880,5435149,13364581,28381270,49366029,121983257,
%U 259326130,454266335,1127069084,2398177242,4225704669,10519451346,22399493726
%N Number of (2+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 2 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 2 3 4 6 or 7
%C Row 2 of A252407
%H R. H. Hardin, <a href="/A252409/b252409.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 20*a(n-3) -124*a(n-6) +249*a(n-9) -145*a(n-12) -58*a(n-15) +74*a(n-18) -15*a(n-21) for n>26
%e Some solutions for n=4
%e ..0..3..1..0..3..1....3..0..0..3..0..0....1..3..0..1..3..0....1..3..3..1..3..3
%e ..3..2..2..3..2..2....2..0..2..2..0..2....2..3..2..2..3..2....2..0..2..2..3..2
%e ..2..3..2..2..3..2....0..0..3..0..0..3....2..2..3..2..2..3....2..2..3..2..2..3
%e ..3..3..1..3..3..1....3..0..0..3..1..0....1..0..3..1..0..3....1..3..3..1..3..3
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 17 2014
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