Triangle read by rows: T(n,k) is the number of Grand Dyck paths of semilength n that cross the x-axis k times (n>=1, k>=0).

A118920

Triangle read by rows: T(n,k) is the number of Grand Dyck paths of semilength n that cross the x-axis k times (n>=1, k>=0).

Terms

    a(0) =2a(1) =4a(2) =2a(3) =10a(4) =8a(5) =2a(6) =28a(7) =28a(8) =12a(9) =2a(10) =84a(11) =96a(12) =54a(13) =16a(14) =2a(15) =264a(16) =330a(17) =220a(18) =88a(19) =20a(20) =2a(21) =858a(22) =1144a(23) =858a(24) =416a(25) =130a(26) =24a(27) =2a(28) =2860a(29) =4004

External references