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Number of n X 4 0..1 arrays with no element equal to a strict majority of its horizontal and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.
1

%I #8 Feb 11 2019 14:25:45

%S 2,4,22,125,717,4121,23690,136181,782826,4500021,25868076,148700951,

%T 854797731,4913749086,28246366671,162372399730,933387168180,

%U 5365515365948,30843315747327,177300792451846,1019202061854748

%N Number of n X 4 0..1 arrays with no element equal to a strict majority of its horizontal and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.

%H R. H. Hardin, <a href="/A279705/b279705.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 10*a(n-1) - 33*a(n-2) + 61*a(n-3) - 78*a(n-4) + 64*a(n-5) - 32*a(n-6) + 9*a(n-7) - a(n-8) for n>9.

%F Empirical g.f.: x*(2 - 16*x + 48*x^2 - 85*x^3 + 105*x^4 - 82*x^5 + 40*x^6 - 11*x^7 + x^8) / (1 - 10*x + 33*x^2 - 61*x^3 + 78*x^4 - 64*x^5 + 32*x^6 - 9*x^7 + x^8). - _Colin Barker_, Feb 11 2019

%e Some solutions for n=4:

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

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

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

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

%Y Column 4 of A279709.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 17 2016