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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A053049 Smallest integer m such that sum_(k=1 to m) phi(k) is divisible by n, where phi(k) is the totient function. 3
1, 2, 4, 3, 5, 4, 9, 10, 7, 5, 8, 6, 46, 9, 19, 10, 18, 7, 60, 16, 11, 8, 12, 15, 22, 46, 29, 9, 13, 19, 51, 10, 36, 18, 21, 15, 88, 60, 142, 16, 67, 11, 23, 31, 24, 12, 55, 17, 40, 22, 18, 153, 26, 29, 184, 75, 84, 13, 92, 19 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

Felice Russo, A set of new Smarandache functions, sequences and conjectures in number theory, American Research Press 2000

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

MATHEMATICA

a[n_] := (m = 1; While[! IntegerQ[Sum[EulerPhi[k], {k, 1, m}]/n], m++]; m); a /@ Range[60] (* Jean-Fran├žois Alcover, Jul 20 2011 *)

PROG

(PARI) a(n)=my(m=1, s=Mod(1, n)); while(s, s+=eulerphi(m++)); m \\ Charles R Greathouse IV, Feb 24 2012

CROSSREFS

Cf. A002034, A011772.

Sequence in context: A060762 A328793 A195782 * A306762 A124938 A198342

Adjacent sequences:  A053046 A053047 A053048 * A053050 A053051 A053052

KEYWORD

easy,nice,nonn

AUTHOR

Felice Russo, Feb 25 2000

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 31 04:27 EDT 2021. Contains 346367 sequences. (Running on oeis4.)