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A218759 Unmatched value maps: number of n X 2 binary arrays indicating the locations of corresponding elements not equal to any horizontal or vertical neighbor in a random 0..1 n X 2 array. 2

%I

%S 2,6,18,47,134,373,1035,2889,8050,22420,62477,174072,484983,1351277,

%T 3764915,10489750,29226504,81430659,226881448,632135485,1761251171,

%U 4907184849,13672362150,38093833868,106136756981,295717444696

%N Unmatched value maps: number of n X 2 binary arrays indicating the locations of corresponding elements not equal to any horizontal or vertical neighbor in a random 0..1 n X 2 array.

%C Column 2 of A218765.

%H R. H. Hardin, <a href="/A218759/b218759.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) + a(n-2) + 3*a(n-3) + 2*a(n-5) + 2*a(n-6) - 2*a(n-7).

%F Empirical g.f.: x*(2 + 2*x + 4*x^2 - x^3 + 4*x^4 - 2*x^6) / (1 - 2*x - x^2 - 3*x^3 - 2*x^5 - 2*x^6 + 2*x^7). - _Colin Barker_, Mar 10 2018

%e Some solutions for n=3:

%e ..1..1....0..0....0..1....0..0....1..0....0..0....0..0....0..1....0..0....0..0

%e ..0..0....0..0....0..0....0..1....0..0....0..0....1..0....0..0....1..0....0..0

%e ..0..0....1..1....1..0....1..1....0..0....1..0....0..0....0..0....1..1....0..0

%Y Cf. A218765.

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 05 2012

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Last modified January 27 17:21 EST 2023. Contains 359845 sequences. (Running on oeis4.)