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%I #8 Jun 28 2018 09:22:39
%S 9,81,225,625,3025,14641,53361,194481,815409,3418801,13359025,
%T 52200625,211266225,855036081,3400172721,13521270961,54243807409,
%U 217611987121,869173967025,3471607400625,13896604674225,55627148806321
%N Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 1 vertically.
%C Row 4 of A208118.
%H R. H. Hardin, <a href="/A208119/b208119.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 5*a(n-1) - 10*a(n-2) + 30*a(n-3) - 120*a(n-5) + 160*a(n-6) - 320*a(n-7) + 256*a(n-8).
%F Empirical g.f.: x*(9 + 36*x - 90*x^2 + 40*x^3 - 280*x^4 + 96*x^5 - 64*x^6 + 256*x^7) / ((1 - x)*(1 - 2*x)*(1 + 2*x)*(1 - 4*x)*(1 + 2*x^2)*(1 + 8*x^2)). - _Colin Barker_, Jun 28 2018
%e Some solutions for n=4:
%e ..1..0..1..1....0..1..1..1....1..0..1..1....1..1..0..1....0..1..1..0
%e ..0..1..1..1....0..1..1..1....0..0..1..1....1..0..1..1....1..0..1..1
%e ..1..0..0..1....0..1..1..1....0..0..1..1....1..0..0..1....0..1..1..0
%e ..0..0..1..1....0..1..1..1....0..0..1..1....0..0..1..1....1..0..1..1
%Y Cf. A208118.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 23 2012
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