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A014231
(Product of 3 successive Catalan numbers)/2.
1
1, 5, 70, 1470, 38808, 1189188, 40489020, 1491345570, 58388438680, 2400295633736, 102692368441936, 4542162450316400, 206643434552856000, 9631060074695610000, 458381806260954003000, 22220282755463598704250, 1094733022441519300455000, 54717445279576990999935000
OFFSET
0,2
LINKS
FORMULA
a(n) = A014228(n)/2.
MAPLE
a:= proc(n) option remember; `if`(n=0, 1,
8*(2*n-1)*(2*n+1)*(2*n+3)*a(n-1)/((n+1)*(n+2)*(n+3)))
end:
seq(a(n), n=0..20); # Alois P. Heinz, Oct 20 2013
MATHEMATICA
Times@@@Partition[CatalanNumber[Range[0, 20]], 3, 1]/2 (* Harvey P. Dale, Apr 10 2013 *)
CROSSREFS
Cf. A000108.
Sequence in context: A151471 A077691 A277301 * A203528 A147629 A274256
KEYWORD
nonn
AUTHOR
STATUS
approved