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A293459
Denominator of probability that a permutation of elements of some subset of set {1,2..n} is a permutation of elements of some set of the form 1..k, k <= n.
2
1, 1, 7, 385, 3628921, 1216452311762688721, 10333147966386144929717742279694909445041, 5989285834984945898036392571843137173092920925318860392502631168811983977451725959000900501504040321
OFFSET
1,3
LINKS
MATHEMATICA
a[n_] := Denominator[Sum[k!, {k, 0, n}]/Sum[Binomial[n, k]!, {k, 0, n}]]; Array[a, 8] (* Amiram Eldar, Sep 21 2019 *)
PROG
(PARI) a(n) = denominator(sum(k=0, n, k!)/sum(k=0, n, binomial(n, k)!)); \\ Michel Marcus, Oct 12 2017
CROSSREFS
Cf. A293458(numerators).
Sequence in context: A299036 A374141 A112905 * A058275 A184954 A185354
KEYWORD
nonn,frac
AUTHOR
Vladimir Shevelev, Oct 09 2017
EXTENSIONS
More terms from Peter J. C. Moses, Oct 09 2017
STATUS
approved