OFFSET
1,1
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
Robert Israel, Table of n, a(n) for n = 1..32
Robert Steinberg, Lectures on Chevalley Groups, Dept. of Mathematics, Yale University, 1967, pp. 130-131.
FORMULA
a(n) = D(3,n) where D(q,n) = q^(n*(n-1)) * (q^n-1) * Product_{k=1..n-1}(q^(2*k)-1). - Sean A. Irvine, Sep 17 2015
MAPLE
f:= n -> 3^(n*(n-1))*(3^n-1)*mul(3^(2*k)-1, k=1..n-1):
map(f, [$1..10]); # Robert Israel, Sep 22 2015
MATHEMATICA
f[m_, n_] := m^(n (n - 1)) (m^n - 1) Product[m^(2 k) - 1, {k, n - 1}];
f[3, #] & /@ Range@ 8 (* Michael De Vlieger, Sep 17 2015 *)
PROG
(PARI) a(n, q=3) = q^(n*(n-1)) * (q^n-1) * prod(k=1, n-1, q^(2*k)-1); \\ Michel Marcus, Sep 17 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
a(8) and formula from Sean A. Irvine, Sep 17 2015
STATUS
approved