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Number of binary arrays indicating the locations of trailing edge maxima of a random length-n 0..1 array extended with zeros and convolved with 1,1,1.
1

%I #9 Aug 16 2018 08:58:26

%S 2,3,4,5,8,12,18,26,40,60,90,134,202,303,454,680,1021,1532,2298,3447,

%T 5173,7762,11646,17473,26218,39338,59023,88558,132875,199368,299135,

%U 448827,673430,1010428,1516066,2274735,3413059,5121022,7683683,11528750

%N Number of binary arrays indicating the locations of trailing edge maxima of a random length-n 0..1 array extended with zeros and convolved with 1,1,1.

%C Column 1 of A222438.

%H R. H. Hardin, <a href="/A222431/b222431.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) - a(n-2) + 2*a(n-4) - 3*a(n-5) + a(n-6) + a(n-7) - 2*a(n-8) + 2*a(n-9) - a(n-11) + a(n-12) - a(n-13).

%F Empirical g.f.: x*(2 - x - 2*x^4 + x^5 + x^6 - x^7 + 2*x^8 - x^9 - x^10 - x^12) / ((1 - x)*(1 + x)*(1 + x^2)*(1 - 2*x + x^2 - x^4 + x^5 - x^7 + x^8 - x^9)). - _Colin Barker_, Aug 16 2018

%e Some solutions for n=7, one extended zero followed by filtered positions:

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

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

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

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

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

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

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

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

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

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

%Y Cf. A222438.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 20 2013