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 A297397 Number of 4 X n 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 neighboring 1. 1

%I

%S 1,20,57,126,700,2569,7779,31081,117084,400727,1478944,5485580,

%T 19599269,71231855,261062287,945122754,3430304343,12504256178,

%U 45424857782,164983194009,600231458537,2182009835511,7929300624520,28830589829675

%N Number of 4 X n 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 neighboring 1.

%H R. H. Hardin, <a href="/A297397/b297397.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + 3*a(n-2) + 24*a(n-3) + 11*a(n-4) - 21*a(n-5) - 67*a(n-6) - 9*a(n-7) - 45*a(n-8).

%F Empirical g.f.: x*(1 + 19*x + 34*x^2 - 15*x^3 - 88*x^4 - 76*x^5 - 54*x^6 - 45*x^7) / (1 - x - 3*x^2 - 24*x^3 - 11*x^4 + 21*x^5 + 67*x^6 + 9*x^7 + 45*x^8). - _Colin Barker_, Feb 28 2019

%e Some solutions for n=5:

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

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

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

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

%Y Row 4 of A297395.

%K nonn

%O 1,2

%A _R. H. Hardin_, Dec 29 2017

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Last modified December 4 02:16 EST 2022. Contains 358544 sequences. (Running on oeis4.)