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 A086568 Smallest number having as many distinct prime factors as n has prime factors, when counted with multiplicity. 3
 1, 2, 2, 6, 2, 6, 2, 30, 6, 6, 2, 30, 2, 6, 6, 210, 2, 30, 2, 30, 6, 6, 2, 210, 6, 6, 30, 30, 2, 30, 2, 2310, 6, 6, 6, 210, 2, 6, 6, 210, 2, 30, 2, 30, 30, 6, 2, 2310, 6, 30, 6, 30, 2, 210, 6, 210, 6, 6, 2, 210, 2, 6, 30, 30030, 6, 30, 2, 30, 6, 30, 2, 2310, 2, 6, 30, 30, 6, 30, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) = n if and only if n = A002110(m) for some m. That is, primorials give the fixed points of this sequence. LINKS Antti Karttunen, Table of n, a(n) for n = 1..2310 FORMULA a(n) = prime(bigomega(n))# = A002110(A001222(n)). For all n >= 1, A001221(a(n)) = A001222(a(n)) = A001222(n). MATHEMATICA Array[Times @@ Prime@ Range@ PrimeOmega@ # &, 79] (* Michael De Vlieger, Sep 25 2017 *) PROG (PARI) A002110(n) = prod(i=1, n, prime(i)); A086568(n) = A002110(bigomega(n)); \\ Antti Karttunen, Jul 07 2017 CROSSREFS Cf. A001221, A001222, A002110, A130675, A292586. Sequence in context: A278162 A187223 A175194 * A239074 A160122 A093656 Adjacent sequences:  A086565 A086566 A086567 * A086569 A086570 A086571 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jan 03 2004 EXTENSIONS Formula corrected and comments edited by Antti Karttunen, Jul 07 2017 STATUS approved

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Last modified December 5 12:04 EST 2021. Contains 349557 sequences. (Running on oeis4.)