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A060856
Multi-dimensional Catalan numbers: diagonal T(n,n+2) of A060854.
3
1, 14, 6006, 140229804, 278607172289160, 67867669180627125604080, 2760171874087743799855959353857200, 24486819823897171791550434989846505231774984000, 59986874261544072491135645330451363110127974096720977464312000
OFFSET
1,2
LINKS
FORMULA
a(n) = 0!*1!*...*(k-1)! *(k*n)! / ( n!*(n+1)!*...*(n+k-1)! ) for k=n+2.
a(n) ~ sqrt(Pi) * exp(n^2/2 + 2*n + 25/12) * n^(n^2 + 2*n + 11/12) / (A * 2^(2*n^2 + 4*n + 17/12)), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant. - Vaclav Kotesovec, Mar 09 2015
a(n) = A039622(n+1) / (n+1). - Tom Copeland, May 30 2022
MATHEMATICA
Table[Product[j!/(n+j)!, {j, 0, n+1}]*(n*(n+2))!, {n, 1, 10}] (* Vaclav Kotesovec, Mar 09 2015 *)
CROSSREFS
Cf. A039622.
Sequence in context: A241326 A344689 A159372 * A030531 A206357 A147686
KEYWORD
nonn,easy
AUTHOR
R. H. Hardin, May 03 2001
STATUS
approved