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A281058 Number of 3 X n 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

%I A281058 #8 Feb 15 2019 10:21:52
%S A281058 0,6,68,239,618,1403,2828,5482,10342,19136,34907,62976,112617,199929,
%T A281058 352771,619208,1081946,1882951,3265367,5644772,9730124,16728760,
%U A281058 28693405,49108842,83882613,143016171,243420929,413658928,701916100,1189400585
%N A281058 Number of 3 X n 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
%H A281058 R. H. Hardin, <a href="/A281058/b281058.txt">Table of n, a(n) for n = 1..210</a>
%F A281058 Empirical: a(n) = 5*a(n-1) - 7*a(n-2) - 2*a(n-3) + 10*a(n-4) - 2*a(n-5) - 5*a(n-6) + a(n-7) + a(n-8) for n>15.
%F A281058 Empirical g.f.: x^2*(6 + 38*x - 59*x^2 - 89*x^3 + 62*x^4 - 51*x^5 + 175*x^6 + 166*x^7 - 217*x^8 - 106*x^9 + 71*x^10 + 21*x^11 - 7*x^12 - x^13) / ((1 - x)^2*(1 - x - x^2)^3). - _Colin Barker_, Feb 15 2019
%e A281058 Some solutions for n=4:
%e A281058 ..0..1..0..0. .0..1..0..0. .0..1..1..0. .0..0..0..0. .0..0..1..1
%e A281058 ..0..1..0..1. .0..1..0..0. .1..0..1..1. .1..0..1..0. .1..0..1..0
%e A281058 ..0..1..1..0. .0..1..1..0. .1..0..1..0. .1..0..1..1. .1..0..0..1
%Y A281058 Row 3 of A281056.
%K A281058 nonn
%O A281058 1,2
%A A281058 _R. H. Hardin_, Jan 13 2017