A252547 - OEIS

%I #4 Dec 18 2014 09:13:37

%S 2142,15480,88146,331884,2576592,15204660,65274264,519308064,

%T 3103786152,14646511152,117255965760,703300899408,3514356996192,

%U 28154584379520,168981193312416,871431684513984,6978394143113472,41882596925317440

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

%C Row 3 of A252544

%H R. H. Hardin, <a href="/A252547/b252547.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 454*a(n-3) -60040*a(n-6) +2444800*a(n-9) -13041664*a(n-12) +16777216*a(n-15)

%e Some solutions for n=3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 18 2014