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A280551 Number of n X 5 0..1 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

%I A280551 #8 Feb 13 2019 12:25:36
%S A280551 2,87,325,832,1764,3438,6386,11506,20389,35757,62317,108150,187115,
%T A280551 322925,556071,955574,1638882,2805542,4794088,8178068,13927945,
%U A280551 23683803,40214243,68187902,115469449,195294823,329919371,556731676,938492304
%N A280551 Number of n X 5 0..1 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
%H A280551 R. H. Hardin, <a href="/A280551/b280551.txt">Table of n, a(n) for n = 1..210</a>
%F A280551 Empirical: a(n) = 6*a(n-1) - 12*a(n-2) + 5*a(n-3) + 12*a(n-4) - 12*a(n-5) - 3*a(n-6) + 6*a(n-7) - a(n-9) for n>12.
%F A280551 Empirical g.f.: x*(2 + 75*x - 173*x^2 - 84*x^3 + 213*x^4 + 193*x^5 - 84*x^6 - 209*x^7 + 64*x^8 + 25*x^9 - 76*x^10 + 2*x^11) / ((1 - x)^3*(1 - x - x^2)^3). - _Colin Barker_, Feb 13 2019
%e A280551 Some solutions for n=4:
%e A280551 ..0..1..0..1..0. .0..1..0..1..0. .0..0..1..1..1. .0..1..1..0..1
%e A280551 ..1..0..1..0..1. .1..1..0..0..1. .1..1..0..1..0. .1..0..0..1..1
%e A280551 ..0..1..1..0..0. .0..1..0..1..0. .0..0..1..0..0. .0..1..1..0..0
%e A280551 ..1..0..1..0..1. .1..0..1..0..1. .1..1..0..1..1. .1..0..0..1..0
%Y A280551 Column 5 of A280554.
%K A280551 nonn
%O A280551 1,1
%A A280551 _R. H. Hardin_, Jan 05 2017