a(n) = Sum_{k=0..n} binomial(n,k)^3 * k!.
A216831
a(n) = Sum_{k=0..n} binomial(n,k)^3 * k!.
Terms
- a(0) =1a(1) =2a(2) =11a(3) =88a(4) =905a(5) =11246a(6) =162607a(7) =2668436a(8) =48830273a(9) =983353690a(10) =21570885011a(11) =511212091952
External references
- oeis: A216831