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A283125 Number of nX3 0..1 arrays with no 1 equal to more than two of its horizontal and vertical neighbors. 1

%I #6 Mar 02 2017 12:24:56

%S 8,57,378,2521,16818,112276,749447,5002276,33388996,222863968,

%T 1487564143,9929138252,66274651117,442367629539,2952699342837,

%U 19708570048557,131550045689409,878065454645686,5860879322317997,39119983879518589

%N Number of nX3 0..1 arrays with no 1 equal to more than two of its horizontal and vertical neighbors.

%C Column 3 of A283130.

%H R. H. Hardin, <a href="/A283125/b283125.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) +7*a(n-2) +25*a(n-3) +18*a(n-4) +12*a(n-5) -20*a(n-6) -15*a(n-7) +3*a(n-8) +2*a(n-9).

%F Empirical: G.f.: -x*(8 +17*x +37*x^2 +32*x^3 -2*x^4 -33*x^5 -12*x^6 +5*x^7 +2*x^8)/(-1 +5*x +7*x^2 +25*x^3 +18*x^4 +12*x^5 -20*x^6 -15*x^7 +3*x^8 +2*x^9) . - _R. J. Mathar_, Mar 02 2017

%e Some solutions for n=4

%e ..1..0..1. .1..0..1. .0..0..1. .0..0..1. .1..1..0. .0..1..0. .1..0..0

%e ..0..0..1. .0..0..0. .0..1..0. .0..1..0. .0..1..1. .0..1..0. .1..0..1

%e ..0..0..0. .1..0..1. .1..0..1. .1..0..0. .1..0..1. .1..1..0. .0..0..1

%e ..0..0..1. .1..1..1. .0..1..0. .1..1..1. .1..1..1. .1..0..1. .0..1..0

%Y Cf. A283130.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 01 2017

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Last modified March 28 16:34 EDT 2024. Contains 371254 sequences. (Running on oeis4.)