a(n) = [x^n] (Sum_{k=0..n} k!*x^k)/(Sum_{k=0..n} k!*(-x)^k).
A303565
a(n) = [x^n] (Sum_{k=0..n} k!*x^k)/(Sum_{k=0..n} k!*(-x)^k).
Terms
- a(0) =1a(1) =2a(2) =2a(3) =10a(4) =18a(5) =202a(6) =418a(7) =8762a(8) =18546a(9) =648842a(10) =1361090a(11) =72858394a(12) =150831762a(13) =11533704106a(14) =23631529186
External references
- oeis: A303565