a(n) = (2*n-1)! / 2^(n-1) if n > 0 and a(0) = 1.
A327021
a(n) = (2*n-1)! / 2^(n-1) if n > 0 and a(0) = 1.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =30a(4) =630a(5) =22680a(6) =1247400a(7) =97297200a(8) =10216206000
External references
- oeis: A327021
A327021
a(n) = (2*n-1)! / 2^(n-1) if n > 0 and a(0) = 1.