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 A281465 Number of n X 4 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards. 1

%I

%S 8,37,39,96,207,405,897,1975,4154,8884,19297,41447,88670,190913,

%T 411053,882410,1895974,4078246,8765802,18835918,40491783,87045948,

%U 187087510,402129300,864407625,1858020929,3993687963,8584396666,18452096569

%N Number of n X 4 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

%H R. H. Hardin, <a href="/A281465/b281465.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + a(n-2) + 4*a(n-3) + a(n-4) - 4*a(n-5) - 5*a(n-6) + 3*a(n-8) for n>10.

%F Empirical g.f.: x*(8 + 29*x - 6*x^2 - 12*x^3 - 84*x^4 - 59*x^5 + 50*x^6 + 90*x^7 + 10*x^8 - 41*x^9) / ((1 - x)*(1 - x^2 - 5*x^3 - 6*x^4 - 2*x^5 + 3*x^6 + 3*x^7)). - _Colin Barker_, Feb 19 2019

%e Some solutions for n=4:

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

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

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

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

%Y Column 4 of A281469.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 22 2017

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Last modified December 7 09:17 EST 2022. Contains 358654 sequences. (Running on oeis4.)