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Pseudoprimes to base 6, written in base 6.
7

%I #26 Jul 25 2021 02:40:18

%S 55,505,1001,1221,2121,5041,5051,5501,10101,12001,15225,20301,21021,

%T 23501,24301,24341,30041,31031,32451,42241,50125,50321,101101,102421,

%U 105131,111111,113425,121001,121101,123041,123321,132305,150135,152021,201201,204445,212121,221001,222401,232401

%N Pseudoprimes to base 6, written in base 6.

%H Amiram Eldar, <a href="/A262103/b262103.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A007092(A005937(n)).

%t base = 6; t = {}; n = 1;

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

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

%t AppendTo[t, FromDigits@IntegerDigits[n, 6]]]]; t

%o (PARI) lista(nn, b=6) = {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

%Y Cf. A007092 (numbers in base 6), A005937 (pseudoprimes to base 6).

%Y Cf. A258189, A262101, A262102, A262104, A262105, A262154.

%K nonn,base

%O 1,1

%A _Abdul Gaffar Khan_, Sep 11 2015