Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A122376
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A122376 Number of prime factors (counted with multiplicity) of the smallest number with exactly n divisors. +0
6
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; listen)
OFFSET

1,3

COMMENT

a(p) = p-1 for prime p.

a(u*v)=a(u)+a(v) for u and v coprime; a(n)=A001222(A130279(n))/2. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 21 2007

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

Adjacent sequences: A122373 A122374 A122375 this_sequence A122377 A122378 A122379

Sequence in context: A089265 A113885 A113886 this_sequence A067240 A126080 A060681

KEYWORD

nonn

AUTHOR

Lekraj Beedassy (blekraj(AT)yahoo.com), Aug 30 2006

EXTENSIONS

More terms from Robert G. Wilson v, Aug 31 2006

Edited and extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Sep 11 2006

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified October 11 09:08 EDT 2008. Contains 144831 sequences.


AT&T Labs Research