A252522 - OEIS

%I #4 Dec 18 2014 07:24:15

%S 2176,9069,39689,96659,581529,2662952,6486931,38674076,177771524,

%T 432970668,2576695286,11849993914,28861601874,171722924036,

%U 789791249282,1923610959226,11444904413552,52638098030182,128205198751454

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

%C Column 7 of A252523

%H R. H. Hardin, <a href="/A252522/b252522.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 86*a(n-3) -1415*a(n-6) +8680*a(n-9) -22666*a(n-12) +28036*a(n-15) -15888*a(n-18) +3168*a(n-21) for n>29

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 18 2014