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%I #12 Jun 21 2018 05:42:57
%S 1,2,6,15,37,90,223,550,1355,3341,8237,20307,50064,123426,304290,
%T 750185,1849478,4559634,11241151,27713513,68323858,168443083,
%U 415273274,1023799191,2524036217,6222664445,15341124083,37821433280,93243546406
%N Number of n X 2 0..1 arrays with every element equal to 1 or 2 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 2 of A300350.
%H R. H. Hardin, <a href="/A300344/b300344.txt">Table of n, a(n) for n = 1..210</a>
%H Simon Plouffe, <a href="http://vixra.org/abs/1409.0048"> Conjectures of the OEIS, as of June 20, 2018.</a>
%F Empirical: a(n) = a(n-1) + 2*a(n-2) + 3*a(n-3) + 2*a(n-4) + a(n-5).
%F Empirical g.f.: -x*(-2*x^4-2*x^3-2*x^2-x-1)/(-x^5-2*x^4-3*x^3-2*x^2-x+1). - _Simon Plouffe_, Jun 20 2018
%e Some solutions for n=5:
%e 0 0 0 1 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1
%e 0 1 0 1 1 0 0 1 1 1 0 1 0 1 1 0 1 1 0 1
%e 1 0 1 0 1 0 0 1 0 1 1 0 0 1 1 1 0 1 0 1
%e 0 1 1 0 1 0 0 1 0 1 0 1 1 0 0 1 0 0 0 0
%e 1 1 1 1 1 1 0 0 0 1 0 1 1 0 0 1 1 1 1 1
%Y Cf. A300350.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 03 2018
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