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A268901 Number of n X 5 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

%I A268901 #8 Jan 16 2019 09:23:30
%S A268901 96,2664,54936,1004184,17194680,282550680,4513169016,70609114584,
%T A268901 1087342615224,16536864398616,248976164499192,3717450986032728,
%U A268901 55118358414612792,812385229848253848,11912420604393611640
%N A268901 Number of n X 5 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.
%H A268901 R. H. Hardin, <a href="/A268901/b268901.txt">Table of n, a(n) for n = 1..210</a>
%F A268901 Empirical: a(n) = 30*a(n-1) - 261*a(n-2) + 540*a(n-3) - 324*a(n-4).
%F A268901 Empirical g.f.: 24*x*(4 - 9*x + 3*x^2 - 18*x^3) / (1 - 15*x + 18*x^2)^2. - _Colin Barker_, Jan 16 2019
%e A268901 Some solutions for n=3:
%e A268901 ..1..2..2..1..2. .2..2..1..0..1. .2..1..0..1..2. .0..1..2..2..1
%e A268901 ..2..2..2..1..0. .2..0..1..0..1. .2..1..0..0..0. .0..1..2..1..0
%e A268901 ..2..2..0..0..0. .1..0..1..0..0. .0..1..0..0..0. .2..2..2..1..0
%Y A268901 Column 5 of A268904.
%K A268901 nonn
%O A268901 1,1
%A A268901 _R. H. Hardin_, Feb 15 2016