

A059910


a(n) = {m : multiplicative order of n mod m = 5}.


3



0, 1, 4, 6, 9, 4, 4, 6, 20, 9, 8, 2, 6, 6, 12, 44, 5, 6, 18, 14, 12, 4, 4, 2, 56, 13, 20, 4, 6, 2, 40, 6, 18, 12, 12, 44, 63, 6, 28, 4, 16, 14, 8, 2, 18, 12, 28, 14, 70, 3, 42, 12, 42, 6, 24, 8, 56, 44, 60, 6, 60, 2, 4, 90, 21, 20, 24, 2, 18, 60, 88, 6, 12, 2, 28, 26, 6, 28, 8, 14, 170
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OFFSET

1,3


COMMENTS

The multiplicative order of a mod m, gcd(a,m) = 1, is the smallest natural number d for which a^d = 1 (mod m).


LINKS

Table of n, a(n) for n=1..81.


FORMULA

a(n) = tau(n^51)tau(n1), where tau(n) = number of divisors of n A000005. Generally, if b(n, r) = {m : multiplicative order of n mod m = r} then b(n, r) = Sum_{dr} mu(d)*tau(n^(r/d)1), where mu(n) = Moebius function A008683.


CROSSREFS

Cf. A059907A059909, A059911A059916, A059499, A059885A059892, A002326, A053446A053453, A055205, A048691, A048785.
Sequence in context: A238167 A307036 A076418 * A019837 A132160 A021217
Adjacent sequences: A059907 A059908 A059909 * A059911 A059912 A059913


KEYWORD

easy,nonn


AUTHOR

Vladeta Jovovic, Feb 08 2001


STATUS

approved



