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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. 1

%I

%S 0,468,4988,10112,22106,46610,87995,159317,282552,495655,864369,

%T 1501627,2601791,4498333,7762266,13369326,22983871,39440039,67556367,

%U 115513187,197179026,336035590,571793109,971529387,1648428839,2793279473

%N 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 Row 6 of A281056.

%H R. H. Hardin, <a href="/A281061/b281061.txt">Table of n, a(n) for n = 1..210</a>

%F 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 Some solutions for n=4

%e ..0..1..0..1. .0..0..1..0. .0..0..1..0. .0..0..1..0. .0..0..1..1

%e ..0..1..0..0. .1..0..1..0. .1..1..0..1. .0..1..0..1. .1..0..0..1

%e ..0..1..1..0. .1..0..1..1. .0..1..0..1. .0..1..0..1. .1..1..0..0

%e ..0..0..0..1. .1..0..1..0. .0..1..0..1. .1..1..0..1. .0..1..1..1

%e ..1..1..0..0. .0..1..0..1. .1..1..0..0. .0..1..0..1. .0..1..0..1

%e ..0..1..1..0. .0..1..0..0. .0..1..1..0. .0..1..0..0. .0..1..1..1

%Y Cf. A281056.

%K nonn

%O 1,2

%A _R. H. Hardin_, Jan 13 2017

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Last modified November 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)