Number of Dyck paths of semilength n having no ascents of length 2 that start at an even level.

A114464

Number of Dyck paths of semilength n having no ascents of length 2 that start at an even level.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =6a(5) =18a(6) =54a(7) =166a(8) =522a(9) =1670a(10) =5418a(11) =17786a(12) =58974a(13) =197226a(14) =664494a(15) =2253390a(16) =7685394a(17) =26345230a(18) =90721362a(19) =313682098a(20) =1088609142a(21) =3790610306a(22) =13239554790a(23) =46371693174a(24) =162835695258a(25) =573160873750

External references