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A272597
Numbers n such that the multiplicative group modulo n is the direct product of 7 cyclic groups.
9
120120, 157080, 175560, 185640, 207480, 212520, 240240, 251160, 267960, 271320, 286440, 291720, 314160, 316680, 326040, 328440, 338520, 341880, 351120, 360360, 367080, 371280, 378840, 394680, 397320, 404040, 408408, 414120, 414960, 425040, 426360, 434280, 442680, 447720, 456456, 462840, 469560, 471240
OFFSET
1,1
COMMENTS
Numbers n such that A046072(n) = 7.
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[5*10^5], A046072[#] == 7&] (* Jean-François Alcover, Dec 22 2021, after Geoffrey Critzer in A046072 *)
PROG
(PARI) for(n=1, 10^6, my(t=#(znstar(n)[2])); if(t==7, 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), A272598 (k=8), A272599 (k=9).
Sequence in context: A234736 A236094 A043622 * A190378 A092015 A250673
KEYWORD
nonn
AUTHOR
Joerg Arndt, May 05 2016
STATUS
approved