

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
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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] (* JeanFrançois 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



