A003795 Order of simple Chevalley group A_n (5).

1, 60, 372000, 7254000000, 56653740000000000, 1383059427750000000000000, 3376566710423156250000000000000000, 25761093646334667714843750000000000000000000, 78616578542037111790447631835937500000000000000000000000

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

References

• J. H. Conway, R. T. Curtis, S. P. Norton, R. A. Parker and R. A. Wilson, ATLAS of Finite Groups. Oxford Univ. Press, 1985 [for best online version see https://oeis.org/wiki/Welcome#Links_to_Other_Sites], p. xvi.
• H. S. M. Coxeter and W. O. J. Moser, Generators and Relations for Discrete Groups, 4th ed., Springer-Verlag, NY, reprinted 1984, p. 131.

Programs

Mathematica

f[m_, n_] := Block[{g, x, y}, g[x_, y_] := x^(y (y + 1)/2) Product[x^k - 1, {k, 2, y + 1}]; g[m, n]/GCD[n + 1, m - 1]]; f[5, #] & /@ Range[0, 8] (* Michael De Vlieger, Sep 18 2015 *)

Formula

a(n) = a(5,n) where a(q,n) is defined in A003793. - Sean A. Irvine, Sep 18 2015

Extensions

a(8) from Sean A. Irvine, Sep 18 2015