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A196701 Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,1,0,4,2 for x=0,1,2,3,4.

%I A196701 #12 May 09 2018 08:17:09
%S A196701 2,11,38,136,488,1744,6208,22202,79292,282984,1010760,3609442,
%T A196701 12887556,46021868,164340008,586827146,2095503116,7482801488,
%U A196701 26720080488,95414259450,340712829860,1216643200052,4344485254120,15513628195858
%N A196701 Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,1,0,4,2 for x=0,1,2,3,4.
%C A196701 Every 0 is next to zero 3's, every 1 is next to one 1's, every 2 is next to two 0's, every 3 is next to three 4's, every 4 is next to four 2's.
%C A196701 Column 2 of A196707.
%H A196701 R. H. Hardin, <a href="/A196701/b196701.txt">Table of n, a(n) for n = 1..200</a>
%F A196701 Empirical: a(n) = a(n-1) +4*a(n-2) +16*a(n-3) +9*a(n-4) -a(n-5) +2*a(n-6) +2*a(n-7) for n>8.
%F A196701 Empirical g.f.: x*(2 + 9*x + 19*x^2 + 22*x^3 + 6*x^4 + 7*x^5 + x^6 - 2*x^7) / (1 - x - 4*x^2 - 16*x^3 - 9*x^4 + x^5 - 2*x^6 - 2*x^7). - _Colin Barker_, May 09 2018
%e A196701 Some solutions for n=4:
%e A196701 ..0..2....0..0....0..0....0..2....1..1....0..0....0..1....0..1....2..0....0..0
%e A196701 ..0..0....2..1....0..2....2..0....0..0....2..0....0..1....0..1....0..0....0..2
%e A196701 ..0..0....0..1....0..1....1..2....1..0....2..0....0..2....0..0....2..2....0..2
%e A196701 ..0..2....0..0....0..1....1..0....1..0....0..0....0..0....0..0....0..0....0..0
%K A196701 nonn
%O A196701 1,1
%A A196701 _R. H. Hardin_, Oct 05 2011