Number of peaks at odd level in all nondecreasing Dyck paths of semilength n. A nondecreasing Dyck path is a Dyck path for which the sequence of the altitudes of the valleys is nondecreasing.
A121483
Number of peaks at odd level in all nondecreasing Dyck paths of semilength n. A nondecreasing Dyck path is a Dyck path for which the sequence of the altitudes of the valleys is nondecreasing.
Terms
- a(0) =1a(1) =2a(2) =6a(3) =19a(4) =56a(5) =167a(6) =487a(7) =1411a(8) =4047a(9) =11527a(10) =32617a(11) =91790a(12) =257065a(13) =716896a(14) =1991792a(15) =5515535a(16) =15227846a(17) =41930133a(18) =115176023a(19) =315676425a(20) =863475561a(21) =2357539227a(22) =6425887551a(23) =17487572124a(24) =47522431681a(25) =128969086382a(26) =349567320762
External references
- oeis: A121483