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A290961 Number of endofunctions on [n] such that the LCM of their cycle lengths equals n. 3
1, 1, 2, 6, 24, 840, 720, 5040, 40320, 59814720, 3628800, 83701537920, 479001600, 26980643289600, 2642646473026560, 1307674368000, 20922789888000, 41837259585747225600, 6402373705728000, 598354114828973074790400, 18160977780223038067507200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..389

FORMULA

a(n) = A222029(n,n).

MAPLE

b:= proc(n, m) option remember; `if`(n=0, x^m, add((j-1)!*

      b(n-j, ilcm(m, j))*binomial(n-1, j-1), j=1..n))

    end:

a:= n-> add(coeff(b(j, 1), x, n)*n^(n-j)*binomial(n-1, j-1), j=0..n):

seq(a(n), n=1..25);

CROSSREFS

Main diagonal of A222029.

Cf. A074351 (the same for permutations).

Sequence in context: A110729 A088258 A227886 * A089718 A123150 A086591

Adjacent sequences:  A290958 A290959 A290960 * A290962 A290963 A290964

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Aug 15 2017

STATUS

approved

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Last modified September 20 10:10 EDT 2019. Contains 327229 sequences. (Running on oeis4.)