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 A201885 Number of zero-sum nX2 -2..2 arrays with every element equal to at least one horizontal or vertical neighbor 1

%I

%S 1,9,63,413,3293,25123,196811,1610765,13183301,109772649,924269015,

%T 7845330131,67157103399,578601709251,5012862231269,43640547493913,

%U 381459159995789,3345900096556721,29435197443234979,259612374333413841

%N Number of zero-sum nX2 -2..2 arrays with every element equal to at least one horizontal or vertical neighbor

%C Column 2 of A201888

%H R. H. Hardin, <a href="/A201885/b201885.txt">Table of n, a(n) for n = 1..128</a>

%e Some solutions for n=6

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

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

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

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_ Dec 06 2011

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Last modified February 2 15:47 EST 2023. Contains 360022 sequences. (Running on oeis4.)