a(n) = 48 * 4^n * (2*n-1)!! * (2*n+3)!! / ((n+2)! * (n+4)!).
A248152
a(n) = 48 * 4^n * (2*n-1)!! * (2*n+3)!! / ((n+2)! * (n+4)!).
Terms
- a(0) =3a(1) =4a(2) =14a(3) =72a(4) =462a(5) =3432a(6) =28314a(7) =252824a(8) =2401828a(9) =23984688a(10) =249554968a(11) =2687515040a(12) =29802622140a(13) =338931781200
External references
- oeis: A248152