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%I #16 Oct 12 2017 19:43:15
%S 2,8,12,14,18,20,24,30
%N Degrees of fundamental invariants of Weyl group W(E_8).
%C a(n) - 1 is the n-th number < 30 that is relatively prime to 30. [_Jonathan Sondow_, Apr 16 2009]
%H H. S. M. Coxeter and W. O. J. Moser, <a href="http://doi.org/10.1007/978-3-662-21943-0">Generators and Relations for Discrete Groups</a>, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 141.
%H G. J. Fox, <a href="/A005793/a005793.pdf">Letter to N. J. A. Sloane, May 1991</a>
%F a(n) = Prime(n+2) + 1, for n = 2, 3, ..., 8. [_Jonathan Sondow_, Apr 16 2009]
%K nonn,fini,full
%O 1,1
%A _N. J. A. Sloane_.