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A108975 Product of all primes with primitive root 2 less than or equal to some prime with primitive root 2. 1
3, 15, 165, 2145, 40755, 1181895, 43730115, 2317696095, 136744069605, 8341388245905, 558873012475635, 46386460035477705, 4685032463583248205, 501298473603407557935, 65670100042046390089485 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The poster by Arnold and Monagan reports that the cyclotomic polynomial of order a(6) is the first cyclotomic polynomial whose height is greater than its order. They also report the height of the cyclotomic polynomial Phi(a(7),x) is greater than the order squared. It is also true that k=a(5) is the least order such that the height of Phi(k,x) is greater than the square root of the order. - T. D. Noe, Apr 22 2008
Partial products of A001122. - Charles R Greathouse IV, Jun 21 2013
LINKS
EXAMPLE
3 is the first prime with primitive root 2, so the first term is 3. 5 is the next prime with primitive root 2, so the next term is 3*5=15. 11 is the next prime with primitive root 2, so the next term is 3*5*11=165.
CROSSREFS
Cf. A001122.
Sequence in context: A304998 A105611 A329557 * A097489 A080696 A015013
KEYWORD
nonn
AUTHOR
Douglas Stones (dssto1(AT)student.monash.edu.au), Jul 27 2005
STATUS
approved

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Last modified April 29 13:17 EDT 2024. Contains 372114 sequences. (Running on oeis4.)