Number of Dyck paths of semilength n, having no ascents and no descents of length 1, and having no peaks at even level.
A167638
Number of Dyck paths of semilength n, having no ascents and no descents of length 1, and having no peaks at even level.
Terms
- a(0) =1a(1) =0a(2) =0a(3) =1a(4) =0a(5) =2a(6) =1a(7) =5a(8) =5a(9) =15a(10) =21a(11) =51a(12) =85a(13) =188a(14) =344a(15) =730a(16) =1407a(17) =2935a(18) =5831a(19) =12094a(20) =24480a(21) =50754a(22) =103995a(23) =216043a(24) =446447a(25) =930206a(26) =1934328a(27) =4043275a(28) =8448882a(29) =17716170
External references
- oeis: A167638