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%I #7 Feb 18 2018 10:02:50
%S 1,3,7,13,25,49,97,191,375,737,1449,2849,5601,11011,21647,42557,83665,
%T 164481,323361,635711,1249775,2456993,4830321,9496161,18668961,
%U 36702211,72154647,141852301,278874281,548252401,1077835841,2118969471,4165784295
%N Hilltop maps: number of n X 1 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or vertical neighbor in a random 0..2 n X 1 array
%C Column 1 of A218206.
%H R. H. Hardin, <a href="/A218199/b218199.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = a(n-1) +a(n-2) +a(n-3) +a(n-4) +a(n-5).
%F Empirical g.f.: x*(1 + x + x^2)^2 / (1 - x - x^2 - x^3 - x^4 - x^5). - _Colin Barker_, Feb 18 2018
%e All solutions for n=3:
%e ..1....0....1....1....0....0....1
%e ..0....0....1....1....1....1....0
%e ..1....1....0....1....1....0....0
%Y cf. A102026.
%K nonn
%O 1,2
%A _R. H. Hardin_, Oct 23 2012
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