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%I #6 Jun 11 2017 20:44:59
%S 1,0,0,3,13,30,61,172,619,2241,7736,25786,85315,286653,986444,3465777,
%T 12342188,44275218,159463056,576136367,2089063623,7607265038,
%U 27829092314,102263653872,377340952123,1397457667346,5192248524833,19348310336881,72292940817636
%N Number of Dyck paths of semilength n such that the minimal number of peaks over all positive levels equals two.
%H Alois P. Heinz, <a href="/A288541/b288541.txt">Table of n, a(n) for n = 2..300</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Lattice_path#Counting_lattice_paths">Counting lattice paths</a>
%e : a(5) = 3:
%e :
%e : /\/\ /\/\ /\/\
%e : /\/\/ \ /\/ \/\ / \/\/\ .
%Y Column k=2 of A288387.
%Y Cf. A000108.
%K nonn
%O 2,4
%A _Alois P. Heinz_, Jun 11 2017
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