A003792 Order of universal Chevalley group A_n (9).

1, 720, 42456960, 203039372390400, 78660280796419613491200, 2468438315722201136962330755072000, 6274437692242927471137606015213542491815936000, 1291851049702792234730057308758464452124128263449062932480000

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.

Links

• Index entries for sequences related to groups.

Crossrefs

Cf. A003787, A003788, A003789, A003790, A003791, A052497, A132037.

Programs

Magma

[&*[(9^n - 9^k): k in [0..n-1]]/8: n in [1..10]]; // Vincenzo Librandi, Sep 19 2015

Mathematica

f[m_, n_] := m^(n (n + 1)/2) Product[m^k - 1, {k, 2, n + 1}];
f[9, #] & /@ Range[0, 7] (* Michael De Vlieger, Sep 18 2015 *)

Formula

Numbers so far appear to equal A052497(n)/8. - Ralf Stephan, Mar 30 2004

a(n) = A(9,n) where A(q,n) is defined in A003787. - Sean A. Irvine, Sep 18 2015

a(n) ~ c * 9^(n*(n+2)), where c = (9/8) * A132037 = 0.9861303982904... . - Amiram Eldar, Jul 07 2025

Extensions

a(7) from Sean A. Irvine, Sep 18 2015