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A281210 Number of 6 X n 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.

%I A281210 #7 Feb 18 2019 08:57:16
%S A281210 0,420,1120,1588,2602,4248,6838,11010,17840,29120,47838,78978,130842,
%T A281210 217250,361188,600860,999718,1663078,2765630,4596962,7636856,12679768,
%U A281210 21040526,34894090,57836514,95810754,158634028,262516660,434214550
%N A281210 Number of 6 X n 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.
%H A281210 R. H. Hardin, <a href="/A281210/b281210.txt">Table of n, a(n) for n = 1..210</a>
%F A281210 Empirical: a(n) = 4*a(n-1) - 4*a(n-2) - 2*a(n-3) + 4*a(n-4) - a(n-6) for n>12.
%F A281210 Empirical g.f.: 2*x^2*(210 - 280*x - 606*x^2 + 785*x^3 + 376*x^4 - 525*x^5 - 39*x^6 + 180*x^7 + 36*x^8 - 6*x^9 - 3*x^10) / ((1 - x)^2*(1 - x - x^2)^2). - _Colin Barker_, Feb 18 2019
%e A281210 Some solutions for n=4:
%e A281210 ..0..1..1..0. .0..0..1..0. .0..0..1..1. .0..0..1..0. .0..1..1..0
%e A281210 ..0..0..1..1. .1..1..0..1. .1..0..0..1. .1..0..1..0. .0..0..1..0
%e A281210 ..1..0..0..1. .0..1..0..1. .1..1..0..0. .0..1..1..0. .1..0..1..0
%e A281210 ..1..1..0..1. .1..0..1..0. .0..1..1..0. .1..0..1..0. .1..1..1..0
%e A281210 ..0..1..1..0. .1..0..1..1. .1..0..1..1. .1..0..1..0. .1..0..1..1
%e A281210 ..0..1..0..1. .1..0..0..1. .1..0..0..1. .1..0..1..1. .1..0..0..1
%Y A281210 Row 6 of A281205.
%K A281210 nonn
%O A281210 1,2
%A A281210 _R. H. Hardin_, Jan 17 2017