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A201797 Number of zero-sum nX2 -2..2 arrays with every element unequal to at most two horizontal and vertical neighbors.

%I A201797 #7 Jul 22 2025 16:20:34
%S A201797 5,85,455,3617,28625,235827,1972115,16703881,142672901,1226999941,
%T A201797 10610923603,92180196507,803840798219,7032319990027,61691173120353,
%U A201797 542479698511869,4780243712781261,42200307665852185,373156481784589911
%N A201797 Number of zero-sum nX2 -2..2 arrays with every element unequal to at most two horizontal and vertical neighbors.
%C A201797 Column 2 of A201803
%H A201797 R. H. Hardin, <a href="/A201797/b201797.txt">Table of n, a(n) for n = 1..126</a>
%e A201797 Some solutions for n=5
%e A201797 ..2.-1...-2..2...-2..2...-1..2...-2..1....1..2....2..2....0..0....0..0...-1.-2
%e A201797 ..2.-1...-2..0....1..1...-1..2....2.-1...-2.-2...-2.-2....2..2....2.-1...-1.-2
%e A201797 ..0..0...-2..0....0..0....1.-2....2.-1....2.-2....2..0....0..0....2.-1....2..0
%e A201797 ..0..0....2..2...-1.-1....1.-2...-2.-2....2.-2....2..0....0.-1...-1.-1....2..0
%e A201797 ..0.-2....1.-1....2.-2....2.-2....1..2....2.-1...-2.-2...-2.-1...-1..1....0..2
%K A201797 nonn
%O A201797 1,1
%A A201797 _R. H. Hardin_ Dec 05 2011