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A281054 Number of nX6 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 A281054 #4 Jan 13 2017 16:57:24
%S A281054 6,251,1403,5400,16875,46610,119205,288527,671451,1515524,3339671,
%T A281054 7217269,15347530,32196671,66765699,137073842,278977066,563443975,
%U A281054 1130260537,2253558987,4468793135,8818038639,17322550753,33890757331
%N A281054 Number of nX6 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 A281054 Column 6 of A281056.
%H A281054 R. H. Hardin, <a href="/A281054/b281054.txt">Table of n, a(n) for n = 1..210</a>
%F A281054 Empirical: a(n) = 3*a(n-1) +3*a(n-2) -11*a(n-3) -9*a(n-4) +15*a(n-5) +20*a(n-6) +3*a(n-7) -18*a(n-8) -27*a(n-9) -9*a(n-10) +15*a(n-11) +20*a(n-12) +12*a(n-13) -7*a(n-15) -6*a(n-16) -3*a(n-17) -a(n-18) for n>21
%e A281054 Some solutions for n=4
%e A281054 ..0..1..0..1..0..1. .0..1..0..1..0..1. .0..0..1..0..1..0. .0..1..0..1..0..1
%e A281054 ..0..1..0..1..0..0. .1..1..0..1..0..1. .1..0..1..0..1..0. .0..1..0..0..1..0
%e A281054 ..1..0..1..0..1..0. .0..1..0..1..0..1. .0..1..1..0..0..1. .0..1..1..0..0..1
%e A281054 ..1..0..1..0..0..1. .1..0..0..1..0..1. .0..0..1..1..0..0. .0..0..1..1..0..0
%Y A281054 Cf. A281056.
%K A281054 nonn
%O A281054 1,1
%A A281054 _R. H. Hardin_, Jan 13 2017