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A281061 Number of 6Xn 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 A281061 #4 Jan 13 2017 17:02:40
%S A281061 0,468,4988,10112,22106,46610,87995,159317,282552,495655,864369,
%T A281061 1501627,2601791,4498333,7762266,13369326,22983871,39440039,67556367,
%U A281061 115513187,197179026,336035590,571793109,971529387,1648428839,2793279473
%N A281061 Number of 6Xn 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.
%C A281061 Row 6 of A281056.
%H A281061 R. H. Hardin, <a href="/A281061/b281061.txt">Table of n, a(n) for n = 1..210</a>
%F A281061 Empirical: a(n) = 6*a(n-1) -12*a(n-2) +5*a(n-3) +12*a(n-4) -12*a(n-5) -3*a(n-6) +6*a(n-7) -a(n-9) for n>19
%e A281061 Some solutions for n=4
%e A281061 ..0..1..0..1. .0..0..1..0. .0..0..1..0. .0..0..1..0. .0..0..1..1
%e A281061 ..0..1..0..0. .1..0..1..0. .1..1..0..1. .0..1..0..1. .1..0..0..1
%e A281061 ..0..1..1..0. .1..0..1..1. .0..1..0..1. .0..1..0..1. .1..1..0..0
%e A281061 ..0..0..0..1. .1..0..1..0. .0..1..0..1. .1..1..0..1. .0..1..1..1
%e A281061 ..1..1..0..0. .0..1..0..1. .1..1..0..0. .0..1..0..1. .0..1..0..1
%e A281061 ..0..1..1..0. .0..1..0..0. .0..1..1..0. .0..1..0..0. .0..1..1..1
%Y A281061 Cf. A281056.
%K A281061 nonn
%O A281061 1,2
%A A281061 _R. H. Hardin_, Jan 13 2017