A204481 - OEIS

%I #5 Mar 31 2012 12:37:02

%S 24718,29959,9290,11364,11338,18410,47369,133889,481694,1808046,

%T 6765672,25621498,97131639,368034455,1395284106,5289949408,

%U 20055106670,76034602906,288269180957,1092909631093,4143534785206,15709333424602

%N Number of (n+2)X8 0..3 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly three ways, and new values 0..3 introduced in row major order

%C Column 6 of A204483

%H R. H. Hardin, <a href="/A204481/b204481.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) +a(n-2) -2*a(n-3) -19*a(n-4) -4*a(n-5) +21*a(n-6) +24*a(n-7) +3*a(n-8) -18*a(n-9) -9*a(n-10) for n>13

%e Some solutions for n=3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 15 2012