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Number of nX2 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors.
1

%I #6 Mar 02 2017 12:34:53

%S 4,11,31,89,251,715,2028,5761,16358,46452,131910,374581,1063696,

%T 3020560,8577449,24357268,69167021,196412696,557750593,1583837157,

%U 4497601906,12771782030,36267864414,102989386002,292457628811,830488149997

%N Number of nX2 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors.

%C Column 2 of A282862.

%H R. H. Hardin, <a href="/A282856/b282856.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +4*a(n-2) +3*a(n-3) +a(n-4) +a(n-5).

%F Empirical: G.f.: -x*(1+x)*(x^3+x^2+3*x+4)/(-1+x+4*x^2+3*x^3+x^4+x^5) . - _R. J. Mathar_, Mar 02 2017

%e Some solutions for n=4

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

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

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

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

%Y Cf. A282862.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 23 2017