a(n+1) = 1 + Sum_{k=0..n} binomial(n,k)*a(k)*a(n-k) for n >= 0 with a(0) = 1.
A054687
a(n+1) = 1 + Sum_{k=0..n} binomial(n,k)*a(k)*a(n-k) for n >= 0 with a(0) = 1.
Terms
- a(0) =1a(1) =2a(2) =5a(3) =19a(4) =99a(5) =653a(6) =5187a(7) =48117a(8) =510271a(9) =6088301a(10) =80716427a(11) =1177130893a(12) =18727404639a(13) =322769897573
External references
- oeis: A054687