This site is supported by donations to The OEIS Foundation.

 Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS". Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A122376 Number of prime factors (counted with multiplicity) of the smallest number with exactly n divisors. 5
 0, 1, 2, 2, 4, 3, 6, 4, 4, 5, 10, 4, 12, 7, 6, 5, 16, 5, 18, 6, 8, 11, 22, 6, 8, 13, 6, 8, 28, 7, 30, 6, 12, 17, 10, 6, 36, 19, 14, 7, 40, 9, 42, 12, 8, 23, 46, 7, 12, 9, 18, 14, 52, 7, 14, 9, 20, 29, 58, 8, 60, 31, 10, 8, 16, 13, 66, 18, 24, 11, 70, 9, 72, 37, 10, 20, 16, 15, 78, 9, 8, 41 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS a(p) = p-1 for prime p. a(n) = A001222(A130279(n))/2. - Reinhard Zumkeller, May 21 2007 This function is not additive; the smallest counterexample is a(40) = 7 != 4 + 4 = a(5) + a(8). - Franklin T. Adams-Watters Jul 10 2009 LINKS FORMULA a(n) = Omega(A005179(n)), where Omega(n) = A001222(n). MATHEMATICA s = { (* terms in A005179 *) }; f[n_] := Plus @@ Last /@ FactorInteger@n; f /@ s (* Robert G. Wilson v, Aug 31 2006 *) CROSSREFS Sequence in context: A113885 A113886 A220096 * A067240 A126080 A060681 Adjacent sequences:  A122373 A122374 A122375 * A122377 A122378 A122379 KEYWORD nonn AUTHOR Lekraj Beedassy, Aug 30 2006 EXTENSIONS More terms from Robert G. Wilson v, Aug 31 2006 Edited and extended by Ray Chandler, Sep 11 2006 Incorrect comment removed by Franklin T. Adams-Watters, Jul 11 2009 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified November 22 15:27 EST 2017. Contains 295089 sequences.