Catalan numbers at triangular positions: a(n) = A000108(n(n+1)/2).

A135758

Catalan numbers at triangular positions: a(n) = A000108(n(n+1)/2).

Terms

    a(0) =1a(1) =1a(2) =5a(3) =132a(4) =16796a(5) =9694845a(6) =24466267020

External references