

A002174


Values taken by reduced totient function psi(n).
(Formerly M0986 N0370)


8



1, 2, 4, 6, 8, 10, 12, 16, 18, 20, 22, 24, 28, 30, 32, 36, 40, 42, 44, 46, 48, 52, 54, 56, 58, 60, 64, 66, 70, 72, 78, 80, 82, 84, 88, 90, 92, 96, 100, 102, 104, 106, 108, 110, 112, 116, 120, 126, 128, 130, 132, 136, 138, 140, 144, 148, 150, 156, 160, 162, 164, 166, 168
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OFFSET

1,2


COMMENTS

If p is a Sophie Germain prime (A005384), then 2p is here.  T. D. Noe, Aug 13 2008
Union[A002322] = A002174.  Vladimir Joseph Stephan Orlovsky, Jul 21 2009


REFERENCES

D. H. Lehmer, Guide to Tables in the Theory of Numbers. Bulletin No. 105, National Research Council, Washington, DC, 1941, pp. 710.
C. Moreau, Sur quelques theoremes d'arithmetique, Nouvelles Annales de MathÃ©matiques, 17 (1898), 293307.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).


LINKS

T. D. Noe, Table of n, a(n) for n = 1..10000
Florian Luca and Carl Pomerance, On the range of Carmichael's universalexponent function, Acta Arithmetica, to appear c. 2014.


FORMULA

n (log n)^0.086 << a(n) << n (log n)^0.36 where << is the Vinogradov symbol, see Luca & Pomerance.  Charles R Greathouse IV, Dec 28 2013


MATHEMATICA

lst={}; Do[p=Prime[n]; AppendTo[lst, CarmichaelLambda[n]], {n, 6*7!}]; lst; Take[Union[lst], 123] (* Vladimir Joseph Stephan Orlovsky, Jul 21 2009 *)


CROSSREFS

Cf. A002322, A002396, A143407, A143408.
Sequence in context: A186384 A011860 A049445 * A002202 A049225 A076450
Adjacent sequences: A002171 A002172 A002173 * A002175 A002176 A002177


KEYWORD

nonn,nice


AUTHOR

N. J. A. Sloane.


EXTENSIONS

More terms from T. D. Noe, Aug 13 2008


STATUS

approved



