login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A085310 Number of distinct 7th powers modulo n. 13
1, 2, 3, 3, 5, 6, 7, 5, 7, 10, 11, 9, 13, 14, 15, 9, 17, 14, 19, 15, 21, 22, 23, 15, 21, 26, 19, 21, 5, 30, 31, 17, 33, 34, 35, 21, 37, 38, 39, 25, 41, 42, 7, 33, 35, 46, 47, 27, 7, 42, 51, 39, 53, 38, 55, 35, 57, 10, 59, 45, 61, 62, 49, 33, 65, 66, 67, 51, 69, 70, 11, 35, 73, 74 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Compare with enigmatic similarity of analogous odd-th power counts to A055653.

This sequence is multiplicative [Li]. - Leon P Smith, Apr 16 2005

LINKS

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

S. Li, On the number of elements with maximal order in the multiplicative group modulo n, Acta Arithm. 86 (2) (1998) 113, see proof of theorem 2.1

MAPLE

A085310 := proc(m)

    {seq( modp(b^7, m), b=0..m-1) };

    nops(%) ;

end proc:

seq(A085310(m), m=1..100) ; # R. J. Mathar, Sep 22 2017

MATHEMATICA

a[n_] := Table[PowerMod[i, 7, n], {i, 0, n - 1}] // Union // Length;

Array[a, 100] (* Jean-Fran├žois Alcover, Mar 24 2020 *)

PROG

(PARI) a(n)=my(f=factor(n)); prod(i=1, #f[, 1], my(k=f[i, 1]^f[i, 2]); #vecsort(vector(k, i, i^7%k), , 8)) \\ Charles R Greathouse IV, Sep 05 2013

CROSSREFS

Cf. A000224[k=2], A046530[k=3], A052273[k=4], A052274[k=5], A052275[k=6], A085311[k=8], A085312[k=9], A085313[k=10], A085314[k=11], A228849[k=12], A055653.

Sequence in context: A331299 A052274 A085314 * A055653 A155918 A344705

Adjacent sequences:  A085307 A085308 A085309 * A085311 A085312 A085313

KEYWORD

nonn,mult

AUTHOR

Labos Elemer, Jun 27 2003

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 January 20 13:06 EST 2022. Contains 350472 sequences. (Running on oeis4.)