A252247 - OEIS

%I #4 Dec 16 2014 07:13:20

%S 318,260,278,352,463,616,847,1160,1625,2281,3237,4631,6575,9496,13664,

%T 19579,28429,41049,59172,86036,124646,180255,262364,381099,552201,

%U 804746,1170960,1699487,2479568,3612216,5250764,7667560,11180674,16274784

%N Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 3 5 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 3 5 6 or 7

%C Column 1 of A252254

%H R. H. Hardin, <a href="/A252247/b252247.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-2) +7*a(n-3) -a(n-4) -11*a(n-5) -19*a(n-6) +4*a(n-7) +21*a(n-8) +26*a(n-9) -4*a(n-10) -18*a(n-11) -19*a(n-12) +a(n-13) +7*a(n-14) +7*a(n-15) -a(n-17) -a(n-18) for n>25

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 16 2014