Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n, having k long ascents (i.e., ascents of length at least 2). Rows are of length 1,1,2,2,3,3,... .
A091156
Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n, having k long ascents (i.e., ascents of length at least 2). Rows are of length 1,1,2,2,3,3,... .
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =4a(6) =1a(7) =11a(8) =2a(9) =1a(10) =26a(11) =15a(12) =1a(13) =57a(14) =69a(15) =5a(16) =1a(17) =120a(18) =252a(19) =56a(20) =1a(21) =247a(22) =804a(23) =364a(24) =14a(25) =1a(26) =502a(27) =2349a(28) =1800a(29) =210
External references
- oeis: A091156