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A005776
Exponents m_i associated with Weyl group W(E_8).
15
1, 7, 11, 13, 17, 19, 23, 29
OFFSET
1,2
COMMENTS
Numbers coprime to 30 in that number's reduced residue system. - Alonso del Arte, Oct 03 2017
REFERENCES
H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 141.
MATHEMATICA
Select[Range[30], GCD[30, #] == 1 &] (* Alonso del Arte, Oct 03 2017 *)
PROG
(Magma) Exponents(RootDatum("E8")); // Sergei Haller (sergei(AT)sergei-haller.de), Dec 21 2006
(PARI) select(n->gcd(n, 30)==1, [1..29]) \\ Charles R Greathouse IV, Oct 17 2017
CROSSREFS
Sequence in context: A191988 A128974 A286609 * A322272 A161850 A007775
KEYWORD
nonn,fini,full
STATUS
approved