a(n) = coefficient of x^n in the n-th iteration (n-fold self-composition) of the g.f. of triangular numbers (A000217).
A302355
a(n) = coefficient of x^n in the n-th iteration (n-fold self-composition) of the g.f. of triangular numbers (A000217).
Terms
- a(0) =1a(1) =6a(2) =72a(3) =1390a(4) =37515a(5) =1307691a(6) =56000728a(7) =2847503268a(8) =167737660533
External references
- oeis: A302355