a(n) = 2^A006218(n)/( (n!)^2*Sum_{m=0..n} 1/(m!*(2*n-m+1)!) ).
A178345
a(n) = 2^A006218(n)/( (n!)^2*Sum_{m=0..n} 1/(m!*(2*n-m+1)!) ).
Terms
- a(0) =1a(1) =3a(2) =15a(3) =70a(4) =630a(5) =2772a(6) =48048a(7) =205920a(8) =3500640a(9) =29560960a(10) =496624128a(11) =2076791808a(12) =138452787200a(13) =575111577600
External references
- oeis: A178345