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A116639 Numbers n such that 13^n == 15 (mod n). 13
1, 2, 14, 22, 1582, 11266, 52766, 76202, 100562, 494371, 641141, 1698494, 66593158, 469296521, 10917186079, 12062558662, 4928050067287, 5315948729617, 29841213777637, 113215787397262, 778590786358582, 787324867879046 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

No other terms below 10^15. Some large terms: 6991413003775539262, 2360895769139218729155198091. - Max Alekseyev, Oct 15 2016

LINKS

Table of n, a(n) for n=1..22.

MATHEMATICA

Select[Range[25000000], PowerMod[13, #, # ]==15&] (* Harvey P. Dale, Feb 03 2009 *)

CROSSREFS

Cf. A116609, A116611, A116620, A116621, A116622, A116629, A116630, A116631, A116632, A116636, A116638.

Sequence in context: A247035 A069512 A328217 * A220274 A036433 A172048

Adjacent sequences:  A116636 A116637 A116638 * A116640 A116641 A116642

KEYWORD

nonn

AUTHOR

Zak Seidov, Feb 19 2006

EXTENSIONS

One more term from Harvey P. Dale, Feb 03 2009

Edited by Max Alekseyev, Sep 19 2009

a(14)-a(22) from Max Alekseyev, May 04 2010, Apr 29 2014, Oct 15 2016

STATUS

approved

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Last modified September 27 08:39 EDT 2021. Contains 347689 sequences. (Running on oeis4.)