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%I #4 Mar 12 2017 14:37:53
%S 0,28,388,7742,61592,700534,6345928,54063960,463390898,3745175778,
%T 29932577562,234328588526,1803842585678,13723043109600,
%U 103162171803860,768173607105144,5671713327162306,41562268140668656,302562753480355030
%N Number of 4Xn 0..1 arrays with no 1 equal to more than one of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly two elements.
%C Row 4 of A283634.
%H R. H. Hardin, <a href="/A283637/b283637.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) +45*a(n-2) -34*a(n-3) -1527*a(n-4) -4200*a(n-5) +5806*a(n-6) +79440*a(n-7) +256035*a(n-8) +556862*a(n-9) +773985*a(n-10) +907686*a(n-11) +67578*a(n-12) -154770*a(n-13) -3028137*a(n-14) -564902*a(n-15) -5353965*a(n-16) +3950340*a(n-17) -4944390*a(n-18) +9675900*a(n-19) -5062575*a(n-20) +8559650*a(n-21) -5818125*a(n-22) +3153750*a(n-23) -3048625*a(n-24) for n>26
%e Some solutions for n=4
%e ..0..0..1..1. .0..1..0..0. .0..0..0..1. .0..1..1..1. .1..0..1..0
%e ..1..0..0..1. .1..1..0..0. .0..1..0..0. .0..0..0..0. .0..0..1..0
%e ..1..0..0..1. .0..1..0..0. .1..0..0..0. .0..1..1..0. .0..0..0..0
%e ..1..1..0..0. .1..0..0..1. .1..1..0..1. .1..0..1..0. .1..1..1..1
%Y Cf. A283634.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 12 2017
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