A252552 - OEIS

%I #4 Dec 18 2014 09:45:58

%S 1107,889,1477,3084,7144,16327,37430,88797,207847,481879,1150442,

%T 2708222,6301644,15085495,35585196,82935199,198783648,469314277,

%U 1094651690,2625103921,6199987115,14467168392,34700770012,81969284111,191315257301

%N Number of (n+2)X(2+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 Column 2 of A252558

%H R. H. Hardin, <a href="/A252552/b252552.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 41*a(n-3) -642*a(n-6) +4961*a(n-9) -21249*a(n-12) +55203*a(n-15) -94450*a(n-18) +115159*a(n-21) -104947*a(n-24) +71287*a(n-27) -34926*a(n-30) +11911*a(n-33) -2699*a(n-36) +381*a(n-39) -30*a(n-42) +a(n-45) for n>50

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 18 2014