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%I #8 Feb 26 2019 14:13:33
%S 1,7,23,66,207,654,2049,6422,20119,63033,197551,619096,1940007,
%T 6079365,19051015,59700283,187082905,586262278,1837172149,5757153010,
%U 18041210871,56535805498,177166451873,555187134041,1739791875173,5451991915452
%N Number of 2 X n 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 or 2 neighboring 1s.
%H R. H. Hardin, <a href="/A297315/b297315.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) - 2*a(n-2) + 8*a(n-3) - 3*a(n-4) + 7*a(n-5) - 5*a(n-6) - a(n-7) - a(n-8) + a(n-9).
%F Empirical g.f.: x*(1 + x - x^2)*(1 + 3*x + 2*x^2 + 4*x^3 - x^5 - x^6) / ((1 - x + 2*x^2 - x^3)*(1 - 2*x - 2*x^2 - 5*x^3 + x^5 + x^6)). - _Colin Barker_, Feb 26 2019
%e Some solutions for n=5:
%e ..1..1..0..1..0. .0..0..0..1..1. .1..1..0..0..0. .0..0..0..1..0
%e ..0..1..1..0..0. .1..1..1..0..0. .0..1..1..1..0. .0..0..1..0..0
%Y Row 2 of A297314.
%K nonn
%O 1,2
%A _R. H. Hardin_, Dec 28 2017
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