%I #4 Dec 01 2014 19:43:46
%S 309,3921,50831,663307,8671957,113445117,1484345363,19422725739,
%T 254151937033,3325670716433,43517693556387,569446264259255,
%U 7451431382751933,97504955911036833,1275891317091048423
%N Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock summing to 3 4 or 5
%C Column 2 of A251351
%H R. H. Hardin, <a href="/A251345/b251345.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 16*a(n-1) -27*a(n-2) -173*a(n-3) +362*a(n-4) -61*a(n-5) -144*a(n-6) +48*a(n-7)
%e Some solutions for n=3
%e ..2..1..2....2..0..2....1..0..1....0..2..1....1..2..1....0..1..0....1..0..2
%e ..0..1..0....1..2..0....1..1..1....0..2..0....1..1..0....1..1..1....2..0..1
%e ..2..1..1....1..0..1....0..1..1....2..1..0....2..1..1....1..2..1....2..1..1
%e ..2..0..1....1..1..2....0..2..1....1..1..1....2..0..1....1..0..2....0..0..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 01 2014