A252565 - OEIS

%I #4 Dec 18 2014 09:55:35

%S 6855,37430,270672,748814,6914968,52263770,145399017,1341388351,

%T 10184411086,28321894951,260779474542,1989505296550,5530905855092,

%U 50840364519758,389496897105008,1082593348176820,9933903062601790

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

%C Row 7 of A252558

%H R. H. Hardin, <a href="/A252565/b252565.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 414*a(n-3) -49716*a(n-6) +1528047*a(n-9) -30967009*a(n-12) +445144640*a(n-15) -3431389746*a(n-18) +11737912047*a(n-21) -18662541672*a(n-24) +16329417636*a(n-27) -9970599024*a(n-30) +4262742720*a(n-33) -681198336*a(n-36) for n>45

%e Some solutions for n=2

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

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

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

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 18 2014