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%I #9 Mar 13 2018 11:12:24
%S 2,9,40,155,617,2457,9785,38986,155300,618678,2464607,9818228,
%T 39112730,155812804,620709233,2472710322,9850500300,39241295090,
%U 156324978076,622749547526,2480838338958,9882879704522,39370284519705,156838831344437
%N Majority value maps: number of n X 2 binary arrays indicating the locations of corresponding elements equal to at least half of their horizontal, vertical and antidiagonal neighbors in a random 0..3 n X 2 array.
%C Column 2 of A220313.
%H R. H. Hardin, <a href="/A220309/b220309.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) + 2*a(n-2) - 8*a(n-3) - 3*a(n-4) + 9*a(n-5) - 2*a(n-6) - 2*a(n-7) - a(n-8) + a(n-9) for n>10.
%F Empirical g.f.: x*(2 + x - 7*x^3 - 5*x^4 + 8*x^5 + 6*x^6 - 5*x^7 - 2*x^8 + x^9) / (1 - 4*x - 2*x^2 + 8*x^3 + 3*x^4 - 9*x^5 + 2*x^6 + 2*x^7 + x^8 - x^9). - _Colin Barker_, Mar 13 2018
%e Some solutions for n=3:
%e ..1..1....1..1....1..1....1..1....0..0....1..1....1..1....1..0....1..1....0..0
%e ..1..0....0..1....0..0....0..0....0..0....1..1....1..1....1..1....1..0....1..0
%e ..0..0....1..1....1..1....0..0....1..1....0..0....1..0....0..1....1..1....1..1
%Y Cf. A220313.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 10 2012
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