cp's OEIS Frontend

A288540 Number of Dyck paths of semilength n such that the minimal number of peaks over all positive levels equals one.

%I A288540 #7 Jun 11 2017 18:19:18
%S A288540 1,0,2,5,13,35,112,368,1208,3992,13449,46187,160804,565535,2005796,
%T A288540 7168058,25793100,93388250,340005973,1244062960,4572478054,
%U A288540 16874672868,62508259095,232338076267,866289458048,3239350667761,12145345634715,45649270140732
%N A288540 Number of Dyck paths of semilength n such that the minimal number of peaks over all positive levels equals one.
%H A288540 Alois P. Heinz, <a href="/A288540/b288540.txt">Table of n, a(n) for n = 1..300</a>
%H A288540 Wikipedia, <a href="https://en.wikipedia.org/wiki/Lattice_path#Counting_lattice_paths">Counting lattice paths</a>
%e A288540 : a(3) = 2:
%e A288540 :
%e A288540 :          /\    /\
%e A288540 :       /\/  \  /  \/\  .
%Y A288540 Column k=1 of A288387.
%Y A288540 Cf. A000108.
%K A288540 nonn
%O A288540 1,3
%A A288540 _Alois P. Heinz_, Jun 11 2017