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A272595
Numbers n such that the multiplicative group modulo n is the direct product of 5 cyclic groups.
9
840, 1320, 1560, 1680, 1848, 2040, 2184, 2280, 2520, 2640, 2760, 2856, 3080, 3120, 3192, 3360, 3432, 3480, 3640, 3696, 3720, 3864, 3960, 4080, 4200, 4368, 4440, 4488, 4560, 4620, 4680, 4760, 4872, 4920, 5016, 5040, 5160, 5208, 5280, 5304, 5320, 5460, 5520, 5544, 5640, 5712, 5720, 5880, 5928, 6072, 6120
OFFSET
1,1
COMMENTS
Numbers n such that A046072(n) = 5.
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[10^4], A046072[#] == 5&] (* Jean-François Alcover, Dec 22 2021, after Geoffrey Critzer in A046072 *)
PROG
(PARI) for(n=1, 10^4, my(t=#(znstar(n)[2])); if(t==5, print1(n, ", ")));
CROSSREFS
Direct product of k groups: A033948 (k=1), A272592 (k=2), A272593 (k=3), A272594 (k=4), A272596 (k=6), A272597 (k=7), A272598 (k=8), A272599 (k=9).
Sequence in context: A144770 A068546 A033269 * A179670 A092002 A169827
KEYWORD
nonn
AUTHOR
Joerg Arndt, May 05 2016
STATUS
approved