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A281211 Number of 7 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 A281211 #7 Feb 18 2019 08:57:22
%S A281211 0,1308,2688,3604,5712,9118,14375,22700,36144,58168,94524,154800,
%T A281211 254959,421560,698756,1159898,1926760,3201376,5318733,8833940,
%U A281211 14666360,24337820,40366132,66914912,110866187,183590176,303864300,502685950,831204864
%N A281211 Number of 7 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 A281211 R. H. Hardin, <a href="/A281211/b281211.txt">Table of n, a(n) for n = 1..210</a>
%F A281211 Empirical: a(n) = 4*a(n-1) - 4*a(n-2) - 2*a(n-3) + 4*a(n-4) - a(n-6) for n>13.
%F A281211 Empirical g.f.: x^2*(1308 - 2544*x - 1916*x^2 + 4664*x^3 + 830*x^4 - 2793*x^5 - 12*x^6 + 920*x^7 + 274*x^8 + 40*x^9 - 18*x^10 - 10*x^11) / ((1 - x)^2*(1 - x - x^2)^2). - _Colin Barker_, Feb 18 2019
%e A281211 Some solutions for n=4:
%e A281211 ..0..1..0..1. .0..0..1..0. .0..0..1..0. .0..1..0..1. .0..1..1..0
%e A281211 ..0..0..0..1. .1..0..1..0. .1..0..1..0. .1..0..1..0. .0..0..1..0
%e A281211 ..0..1..0..1. .1..1..1..0. .0..1..0..1. .1..0..1..0. .1..0..1..0
%e A281211 ..0..1..0..0. .0..0..1..0. .0..1..0..1. .1..0..1..0. .0..1..0..1
%e A281211 ..0..1..1..0. .1..0..1..0. .0..0..1..0. .0..1..1..0. .0..1..1..1
%e A281211 ..0..0..1..0. .1..0..1..0. .1..0..1..0. .0..0..1..0. .0..1..0..1
%e A281211 ..1..0..1..1. .0..1..0..1. .0..1..0..1. .1..0..1..0. .0..1..0..0
%Y A281211 Row 7 of A281205.
%K A281211 nonn
%O A281211 1,2
%A A281211 _R. H. Hardin_, Jan 17 2017