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A272598
Numbers n such that the multiplicative group modulo n is the direct product of 8 cyclic groups.
9
2042040, 2282280, 2762760, 2984520, 3483480, 3527160, 3612840, 3723720, 4037880, 4084080, 4269720, 4444440, 4555320, 4564560, 4772040, 4869480, 4924920, 5091240, 5165160, 5383560, 5442360, 5525520, 5542680, 5645640, 5754840, 5811960, 5969040, 6016920, 6126120, 6163080, 6240360, 6366360, 6431880, 6440280
OFFSET
1,1
COMMENTS
Numbers n such that A046072(n) = 8.
MATHEMATICA
A046072[n_] := Which[n == 1 || n == 2, 1,
OddQ[n], PrimeNu[n],
EvenQ[n] && !Divisible[n, 4], PrimeNu[n] - 1,
Divisible[n, 4] && !Divisible[n, 8], PrimeNu[n],
Divisible[n, 8], PrimeNu[n] + 1];
Select[Range[120, 120*10^5, 120], A046072[#] == 8&] (* Jean-François Alcover, Dec 22 2021, after Geoffrey Critzer in A046072 *)
PROG
(PARI) for(n=1, 10^7, my(t=#(znstar(n)[2])); if(t==8, print1(n, ", ")));
CROSSREFS
Direct product of k groups: A033948 (k=1), A272592 (k=2), A272593 (k=3), A272594 (k=4), A272595 (k=5), A272596 (k=6), A272597 (k=7), A272599 (k=9).
Sequence in context: A263892 A163682 A045871 * A190316 A034639 A206667
KEYWORD
nonn
AUTHOR
Joerg Arndt, May 05 2016
STATUS
approved