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A262101 Pseudoprimes to base 4, written in base 4. 0
33, 1111, 1123, 11111, 12303, 13003, 20301, 22011, 22333, 101101, 103133, 103313, 111223, 120231, 122133, 123001, 131203, 131301, 133333, 200113, 212201, 222031, 230011, 300331, 303031, 310213, 321203, 333001, 1010101, 1010103, 1021021, 1022323, 1023323, 1111111, 1112233, 1213021, 1213303, 1330111, 2002001, 2010201, 2013313, 2023033, 2031211, 2032223 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..44.

FORMULA

a(n) = A007090(A020136(n)).

MATHEMATICA

BaseForm[Select[Range[4096], Not[PrimeQ[#]] && PowerMod[4, # - 1, #] == 1 &], 4]

PROG

(PARI) lista(nn, b=4) = {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. A007090 (numbers in base 4), A020136 (pseudoprimes to base 4).

Sequence in context: A293693 A187539 A130835 * A077420 A158688 A294436

Adjacent sequences:  A262098 A262099 A262100 * A262102 A262103 A262104

KEYWORD

nonn,base

AUTHOR

Abdul Gaffar Khan, Sep 11 2015

STATUS

approved

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Last modified July 5 21:00 EDT 2020. Contains 335473 sequences. (Running on oeis4.)