login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A258189 Pseudoprimes to base 3, written in base 3. 0
10101, 11111, 101121, 220212, 222001, 1022011, 1111221, 2010002, 2101001, 2121001, 10101022, 10122201, 10201001, 10212111, 11111112, 11121201, 12010221, 20210202, 21121121, 100001111, 101010101, 102112011, 110020001, 112112001, 12000211, 122000101, 201201201, 202212002 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..28.

FORMULA

a(n) = A007089(A005935(n)). - Michel Marcus, Sep 11 2015

MATHEMATICA

base = 3; t = {}; n = 1;

While[Length[t] < 40, n++;

If[! PrimeQ[n] && PowerMod[base, n - 1, n] == 1,

  AppendTo[t, FromDigits@IntegerDigits[n, 3]]]]; t

PROG

(PARI) lista(nn, b=3) = {for (n=1, nn, if (Mod(b, n)^(n-1)==1 && !ispseudoprime(n) && n>1, print1(subst(Pol(digits(n, b), x), x, 10), ", "); ); ); } \\ Michel Marcus, Sep 30 2015

CROSSREFS

Cf. A005935 (pseudoprimes to base 3), A007089 (numbers in base 3).

Sequence in context: A043641 A210890 A210892 * A114385 A267680 A267876

Adjacent sequences:  A258186 A258187 A258188 * A258190 A258191 A258192

KEYWORD

nonn,base

AUTHOR

Abdul Gaffar Khan, Sep 11 2015

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 November 13 20:57 EST 2019. Contains 329106 sequences. (Running on oeis4.)