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A211242
Order of 6 mod n-th prime: least k such that prime(n) divides 6^k-1.
12
0, 0, 1, 2, 10, 12, 16, 9, 11, 14, 6, 4, 40, 3, 23, 26, 58, 60, 33, 35, 36, 78, 82, 88, 12, 10, 102, 106, 108, 112, 126, 130, 136, 23, 37, 150, 156, 27, 83, 43, 178, 60, 19, 96, 14, 198, 105, 222, 226, 228, 232, 17, 20, 250, 256, 131, 134, 270, 276, 56, 141
OFFSET
1,4
MAPLE
A211242 := proc(n)
if n<= 2 then
0 ;
else
numtheory[order](6, ithprime(n)) ;
end if;
end proc:
seq(A211242(n), n=1..80) ; # R. J. Mathar, Jul 17 2024
MATHEMATICA
nn = 6; Table[If[Mod[nn, p] == 0, 0, MultiplicativeOrder[nn, p]], {p, Prime[Range[100]]}]
PROG
(GAP) A000040:=Filtered([1..350], IsPrime);;
List([1..Length(A000040)], n->OrderMod(6, A000040[n])); # Muniru A Asiru, Feb 06 2019
(PARI) a(n, {base=6}) = my(p=prime(n)); if(base%p, znorder(Mod(base, p)), 0) \\ Jianing Song, May 13 2024
CROSSREFS
Cf. A019336 (full reptend primes in base 6).
Sequence in context: A057989 A050978 A053449 * A060248 A092385 A104238
KEYWORD
nonn,easy
AUTHOR
T. D. Noe, Apr 11 2012
STATUS
approved