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%I #13 Feb 20 2018 04:35:46
%S 1,3,7,13,23,49,95,177,359,705,1351,2689,5303,10321,20423,40353,79223,
%T 156657,309991,611713,1210967,2399761,4750919,9419937,18694199,
%U 37092657,73659175,146373313,290909975,578470225,1150862855,2290191585,4559123447
%N Number of n X 2 0..1 arrays with every element equal to 1, 2 or 4 king-move adjacent elements, with upper left element zero.
%C Column 2 of A297858.
%H R. H. Hardin, <a href="/A297852/b297852.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) - 2*a(n-2) + 4*a(n-3) - 10*a(n-4) + 4*a(n-5) for n>6.
%F Empirical g.f.: x*(1 - 6*x^3 - 4*x^4 + 4*x^5) / ((1 - 2*x)*(1 - x - 4*x^3 + 2*x^4)). - _Colin Barker_, Feb 19 2018
%e Some solutions for n=7:
%e ..0..1. .0..1. .0..1. .0..0. .0..1. .0..1. .0..0. .0..0. .0..1. .0..0
%e ..0..1. .1..0. .0..1. .1..0. .0..1. .0..1. .1..1. .1..1. .0..1. .0..1
%e ..0..1. .1..0. .1..0. .1..1. .0..1. .0..1. .0..1. .1..0. .1..0. .1..1
%e ..1..0. .0..1. .0..1. .1..1. .1..0. .0..1. .0..0. .0..0. .1..0. .0..0
%e ..1..0. .0..1. .0..1. .1..0. .1..0. .1..0. .0..0. .0..0. .1..0. .1..1
%e ..0..1. .0..1. .0..1. .0..0. .0..1. .1..0. .1..0. .0..1. .0..1. .0..1
%e ..1..0. .1..0. .0..1. .1..1. .0..1. .1..0. .1..1. .1..1. .0..1. .0..0
%Y Cf. A297858.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 07 2018
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