O.g.f.: Sum_{n>=0} x^n * Product_{k=1..n} (k^2 + x)/(1 + k^2*x).
A230682
O.g.f.: Sum_{n>=0} x^n * Product_{k=1..n} (k^2 + x)/(1 + k^2*x).
Terms
- a(0) =1a(1) =1a(2) =4a(3) =21a(4) =181a(5) =2320a(6) =41581a(7) =991821a(8) =30339364a(9) =1156828681a(10) =53761779721
External references
- oeis: A230682