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%I #5 Mar 06 2017 17:03:05
%S 0,1,3,19,91,399,1734,7257,29754,120018,477678,1880898,7339875,
%T 28425538,109368210,418413378,1592767290,6036395895,22786979315,
%U 85714057229,321381104832,1201482684424,4479736531496,16661729383449,61830609817953
%N Number of nX2 0..1 arrays with no 1 equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements.
%C Column 2 of A283386.
%H R. H. Hardin, <a href="/A283380/b283380.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 9*a(n-1) -24*a(n-2) +18*a(n-3) -36*a(n-4) +111*a(n-5) -38*a(n-6) +150*a(n-7) -162*a(n-8) +135*a(n-9) -222*a(n-10) +177*a(n-11) -212*a(n-12) +186*a(n-13) -168*a(n-14) +160*a(n-15) -114*a(n-16) +99*a(n-17) -68*a(n-18) +48*a(n-19) -30*a(n-20) +16*a(n-21) -9*a(n-22) +3*a(n-23) -a(n-24)
%e Some solutions for n=4
%e ..0..1. .1..1. .0..0. .0..1. .1..1. .1..1. .0..1. .1..1. .1..1. .1..1
%e ..0..0. .1..1. .0..1. .1..1. .1..0. .0..0. .1..1. .0..1. .1..1. .1..1
%e ..1..1. .0..0. .1..1. .0..1. .1..1. .1..1. .1..0. .1..1. .0..0. .0..0
%e ..1..1. .0..1. .1..0. .1..1. .1..0. .1..1. .0..0. .0..1. .0..0. .1..0
%Y Cf. A283386.
%K nonn
%O 1,3
%A _R. H. Hardin_, Mar 06 2017
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