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!)
 A048049 Denominator of Sum_{k=1..n} 1/phi(k). 8
 1, 1, 2, 1, 4, 4, 12, 6, 3, 12, 60, 15, 60, 60, 120, 30, 240, 80, 720, 720, 720, 720, 7920, 7920, 1584, 1584, 1584, 1584, 11088, 11088, 55440, 13860, 1386, 11088, 11088, 11088, 11088, 11088, 11088, 5544, 6930, 13860, 13860, 3465, 27720, 27720, 637560, 1275120, 182160 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 REFERENCES D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, Section I.27. LINKS Robert Israel, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Totient Summatory Function EXAMPLE 1, 2, 5/2, 3, 13/4, 15/4, 47/12, 25/6, 13/3, 55/12, 281/60, 74/15, ... MAPLE map(denom, ListTools:-PartialSums(map(1/numtheory:-phi, [\$1..100]))); # Robert Israel, Apr 16 2019 CROSSREFS Cf. A000010, A028415. Sequence in context: A034409 A209478 A211178 * A212716 A057772 A145861 Adjacent sequences:  A048046 A048047 A048048 * A048050 A048051 A048052 KEYWORD nonn,frac AUTHOR N. J. A. Sloane, Jun 28 2002 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 April 22 18:24 EDT 2021. Contains 343177 sequences. (Running on oeis4.)