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A246292
Number of permutations on [n*(n+1)/2] with cycles of n distinct lengths.
4
1, 1, 3, 120, 151200, 10897286400, 70959641905152000, 60493719168990845337600000, 9226024969987629401488081551360000000, 329646772667218349211759153151614073700352000000000, 3498788402132461399351052923160966975192989707740695756800000000000
OFFSET
0,3
LINKS
FORMULA
a(n) = C(n+1,2)! / n!.
a(n) = A218868(n*(n+1)/2,n) = A218868(A000217(n),n).
a(n) = A242027(n*(n+1)/2,n) = A242027(A000217(n),n).
a(n) = A022915(n) * A000178(n-1) for n>0.
MAPLE
a:= n-> binomial(n+1, 2)!/n!:
seq(a(n), n=0..12);
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Aug 21 2014
STATUS
approved