O.g.f.: Sum_{n>=0} 2*(n+2)^(n-1) * x^n / Product_{k=1..n} (1+k*x).
A196555
O.g.f.: Sum_{n>=0} 2*(n+2)^(n-1) * x^n / Product_{k=1..n} (1+k*x).
Terms
- a(0) =1a(1) =2a(2) =6a(3) =28a(4) =186a(5) =1614a(6) =17332a(7) =222254a(8) =3317326a(9) =56532264a(10) =1083571422a(11) =23081180918a(12) =541047188936
External references
- oeis: A196555