a(n) = [x^n] (2*n)! * Sum_{k=0..2*n} binomial(x,k).
A347987
a(n) = [x^n] (2*n)! * Sum_{k=0..2*n} binomial(x,k).
Terms
- a(0) =1a(1) =1a(2) =11a(3) =-75a(4) =3969a(5) =-140595a(6) =7374191a(7) =-435638203a(8) =30421321073
External references
- oeis: A347987