A205824 (3n)!/[3n*n!*(n+1)!]

1, 10, 280, 13860, 1009008, 98017920, 11972188800, 1766895530400, 306261891936000, 61040779261862400, 13761921142674432000, 3464298995338621440000, 963455812901426718720000, 293441113300834537758720000

Offset

1,2

Links

Table of n, a(n) for n=1..14.

Mathematica

Table[(3n)!/(3n*n!*(n+1)!), {n, 1, 14}]

Crossrefs

Sequence in context: A117654 A067427 A157713 * A251580 A165457 A025035

Adjacent sequences: A205821 A205822 A205823 * A205825 A205826 A205827

Keyword

nonn

Author

Clark Kimberling, Feb 01 2012

Status

approved