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 A296329 Number of n X 2 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 0 or 2 neighboring 1s. 2

%I #9 Mar 22 2018 09:47:35

%S 3,8,19,47,116,286,705,1738,4285,10564,26044,64208,158296,390257,

%T 962125,2371987,5847808,14416967,35543051,87626508,216031114,

%U 532595025,1313039846,3237119305,7980672808,19675252120,48506630368,119586431488

%N Number of n X 2 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 0 or 2 neighboring 1s.

%C Column 2 of A296335.

%H R. H. Hardin, <a href="/A296329/b296329.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + 2*a(n-2) + 3*a(n-3) + 2*a(n-4) + a(n-5).

%F Empirical g.f.: x*(3 + 5*x + 5*x^2 + 3*x^3 + x^4) / (1 - x - 2*x^2 - 3*x^3 - 2*x^4 - x^5). - _Colin Barker_, Mar 22 2018

%e Some solutions for n=5:

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

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

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

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

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

%Y Cf. A296335.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 10 2017

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Last modified December 3 02:05 EST 2023. Contains 367530 sequences. (Running on oeis4.)