G.f.: 1/(1-x) = Sum_{n>=0} a(n) * x^n*(1-x)^n / Product_{k=1..n-1} (1 + k*x).
A185054
G.f.: 1/(1-x) = Sum_{n>=0} a(n) * x^n*(1-x)^n / Product_{k=1..n-1} (1 + k*x).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =7a(4) =35a(5) =226a(6) =1780a(7) =16489a(8) =175191a(9) =2095995a(10) =27844858a(11) =406243180a(12) =6451271440a(13) =110696475526
External references
- oeis: A185054