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Number of binary arrays indicating the locations of trailing edge maxima of a random length-n 0..7 array extended with zeros and convolved with 1,2,1.
1

%I #8 Aug 15 2018 12:38:33

%S 2,3,4,8,12,19,31,49,80,128,207,334,536,866,1394,2248,3624,5839,9414,

%T 15169,24452,39411,63521,102387,165020,265982,428703,690979,1113717,

%U 1795071,2893285,4663357,7516351,12114776,19526459,31472549,50727107

%N Number of binary arrays indicating the locations of trailing edge maxima of a random length-n 0..7 array extended with zeros and convolved with 1,2,1.

%C Column 7 of A222127.

%H R. H. Hardin, <a href="/A222126/b222126.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + a(n-3) + a(n-5) + 3*a(n-7) - 2*a(n-8) - a(n-10) - a(n-12) - 2*a(n-14) + a(n-15).

%F Empirical g.f.: x*(2 + x + x^2 + 2*x^3 + x^4 + x^5 + x^6 - 4*x^7 - x^8 - x^9 - 3*x^10 - x^11 - 2*x^12 - x^13 + x^14) / ((1 - x)*(1 + x + x^2 + x^3 + x^4 + x^5 + x^6)*(1 - x - x^3 - x^5 - 2*x^7 + x^8)). - _Colin Barker_, Aug 15 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 ..1....0....0....0....0....0....0....0....1....1....0....0....1....0....0....0

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

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

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

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

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

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

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

%Y Cf. A222127.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 08 2013