The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A066504 Sum of n/p^k over all maximal prime-power divisors of n. 3
 0, 1, 1, 1, 1, 5, 1, 1, 1, 7, 1, 7, 1, 9, 8, 1, 1, 11, 1, 9, 10, 13, 1, 11, 1, 15, 1, 11, 1, 31, 1, 1, 14, 19, 12, 13, 1, 21, 16, 13, 1, 41, 1, 15, 14, 25, 1, 19, 1, 27, 20, 17, 1, 29, 16, 15, 22, 31, 1, 47, 1, 33, 16, 1, 18, 61, 1, 21, 26, 59, 1, 17, 1, 39, 28, 23, 18, 71, 1, 21, 1, 43, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,6 COMMENTS a(A000961(m)) = 1; a(A001358(m)) = A008472(A001358(m)). REFERENCES R. K. Guy, Unsolved Problems in Number Theory, B8. LINKS Harry J. Smith, Table of n, a(n) for n = 1..1000 EXAMPLE a(120) = 120/2^3 + 120/3^1 + 120/5^1 = 15 + 40 + 24 = 79. MATHEMATICA f[n_ ] := n*Plus @@ (1/#[[1]]^#[[2]] & /@ FactorInteger@n); Array[f, 83] (* Robert G. Wilson v *) PROG (PARI) { for (n=1, 1000, f=factor(n); a=sum(i=1, matsize(f)[1], n/(f[i, 1]^f[i, 2])); write("b066504.txt", n, " ", a) ) } \\ Harry J. Smith, Feb 18 2010 CROSSREFS Cf. A005236. Cf. A028236. - R. J. Mathar, Sep 30 2008 Sequence in context: A250097 A028235 A028236 * A292771 A322837 A168677 Adjacent sequences:  A066501 A066502 A066503 * A066505 A066506 A066507 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jan 04 2002 EXTENSIONS More terms from Robert G. Wilson v, Dec 06 2005 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified February 26 21:58 EST 2020. Contains 332295 sequences. (Running on oeis4.)