a(n) = [x^n] (2*n)! * Sum_{k=0..2*n} binomial(x+k,k).
A347989
a(n) = [x^n] (2*n)! * Sum_{k=0..2*n} binomial(x+k,k).
Terms
- a(0) =1a(1) =5a(2) =71a(3) =1665a(4) =54649a(5) =2310945a(6) =119753843a(7) =7353403057a(8) =522289211873
External references
- oeis: A347989