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A005796
Degrees of fundamental invariants of Weyl group W(E_8).
3
2, 8, 12, 14, 18, 20, 24, 30
OFFSET
1,1
COMMENTS
a(n) - 1 is the n-th number < 30 that is relatively prime to 30. [Jonathan Sondow, Apr 16 2009]
LINKS
H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 141.
G. J. Fox, Letter to N. J. A. Sloane, May 1991 [The notes on this letter reference this A-number but actually it contains a different sequence, which is not currently in the OEIS. - Andrey Zabolotskiy, Dec 09 2024]
FORMULA
a(n) = Prime(n+2) + 1, for n = 2, 3, ..., 8. [Jonathan Sondow, Apr 16 2009]
CROSSREFS
Sequence in context: A043377 A107629 A080058 * A086173 A108725 A277568
KEYWORD
nonn,fini,full,changed
STATUS
approved