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A262102 Pseudoprimes to base 5, written in base 5. 0
4, 444, 1332, 4221, 11111, 22131, 23404, 30031, 42241, 112443, 133321, 134421, 140122, 140411, 202401, 214244, 222223, 224104, 241121, 304011, 323131, 331401, 402201, 404041, 411313, 421411, 434411, 1001001, 1001331, 1010142, 1032032, 1140421, 1212131, 1224103, 1233321, 1302302, 1302401, 1414331, 1421124, 1440143 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..40.

FORMULA

a(n) = A007091(A005936(n)).

MATHEMATICA

base = 5; t = {}; n = 1;

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

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

  AppendTo[t, FromDigits@IntegerDigits[n, 5]]]]; t

PROG

(PARI) lista(nn, b=5) = {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. A007091 (numbers in base 5), A005936 (pseudoprimes to base 5).

Sequence in context: A159514 A217269 A034985 * A104690 A300507 A215220

Adjacent sequences:  A262099 A262100 A262101 * A262103 A262104 A262105

KEYWORD

nonn,base

AUTHOR

Abdul Gaffar Khan, Sep 11 2015

STATUS

approved

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Last modified June 12 12:53 EDT 2021. Contains 344947 sequences. (Running on oeis4.)