%I #4 Nov 08 2016 08:34:06
%S 0,52,866,16583,316432,6031565,114975158,2191741025,41780404363,
%T 796445224559,15182359059263,289416039476474,5517037468209865,
%U 105169369667173021,2004807177668663124,38216943130107881653
%N Number of nX3 0..2 arrays with every element plus 1 mod 3 equal to some element at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) (1,-1) or (1,0), with upper left element zero.
%C Column 3 of A278006.
%H R. H. Hardin, <a href="/A278001/b278001.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 18*a(n-1) +21*a(n-2) +15*a(n-3) -530*a(n-4) -562*a(n-5) +986*a(n-6) +5831*a(n-7) -1452*a(n-8) -8962*a(n-9) -19556*a(n-10) +24096*a(n-11) +21600*a(n-12) +12480*a(n-13) -45824*a(n-14) +3456*a(n-15) -768*a(n-16)
%e Some solutions for n=4
%e ..0..2..1. .0..2..1. .0..1..0. .0..1..2. .0..1..2. .0..0..1. .0..1..0
%e ..1..2..1. .1..2..0. .2..0..2. .2..0..2. .0..1..0. .1..2..1. .0..2..1
%e ..0..1..0. .2..0..1. .2..0..2. .1..2..2. .2..2..0. .1..0..1. .1..0..0
%e ..2..1..2. .1..1..0. .1..1..1. .1..1..1. .1..1..2. .0..0..0. .2..1..2
%Y Cf. A278006.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 08 2016
|