A207996 - OEIS

%I #12 Nov 23 2015 09:00:12

%S 32,729,17749,441090,11045757,277458045,6978332618,175605187731,

%T 4419979346851,111261280858024,2800819361992659,70507189155056781,

%U 1774944424628356230,44682493917576202087,1124839588414204665607

%N Number of nX7 0..2 arrays with new values 0..2 introduced in row major order and no element equal to any horizontal or vertical neighbor (colorings ignoring permutations of colors).

%C Column 7 of A207997.

%H R. H. Hardin, <a href="/A207996/b207996.txt">Table of n, a(n) for n = 1..210</a>

%F a(n) = 55*a(n-1) -1109*a(n-2) +11330*a(n-3) -67206*a(n-4) +247404*a(n-5) -582440*a(n-6) +881876*a(n-7) -846764*a(n-8) +499200*a(n-9) -172400*a(n-10) +33152*a(n-11) -3264*a(n-12) +128*a(n-13).

%F G.f.: -x*(32 -1031*x +13142*x^2 -89204*x^3 +360470*x^4 -909704*x^5 +1454814*x^6 -1461492*x^7 +896144*x^8 -320568*x^9 +63472*x^10 -6400*x^11 +256*x^12) / ( -1 +55*x -1109*x^2 +11330*x^3 -67206*x^4 +247404*x^5 -582440*x^6 +881876*x^7 -846764*x^8 +499200*x^9 -172400*x^10 +33152*x^11 -3264*x^12 +128*x^13 ). - _R. J. Mathar_, Nov 23 2015

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 22 2012