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A121858 Smallest odd number having prime(n) divisors, where prime(n) is the n-th prime=A000040(n). 1
3, 9, 81, 729, 59049, 531441, 43046721, 387420489, 31381059609, 22876792454961, 205891132094649, 150094635296999121, 12157665459056928801, 109418989131512359209, 8862938119652501095929, 6461081889226673298932241 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(n) is also the smallest number k with the property that the symmetric representation of sigma(k) has prime(n) subparts. - Omar E. Pol, Oct 08 2022
LINKS
FORMULA
a(n) = 3^(prime(n)-1) = 3^A006093(n).
a(n) = A038547(A000040(n)). - Omar E. Pol, Oct 08 2022
MATHEMATICA
3^(Prime[Range[20]]-1) (* Harvey P. Dale, Mar 19 2013 *)
CROSSREFS
Sequence in context: A055156 A047912 A078684 * A215114 A032108 A216206
KEYWORD
nonn
AUTHOR
Lekraj Beedassy, Aug 30 2006
STATUS
approved

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Last modified February 20 21:52 EST 2024. Contains 370219 sequences. (Running on oeis4.)