OFFSET
0,1
COMMENTS
Number of conjugacy classes in Ree group 2G2(3*9^n).
LINKS
Eric M. Schmidt, Table of n, a(n) for n = 0..1000
Frank Luebeck, Numbers of Conjugacy Classes in Finite Groups of Lie Type.
Index entries for linear recurrences with constant coefficients, signature (10,-9).
FORMULA
G.f.: 8/(1-x) + 3/(1-9*x).
a(n) = 10*a(n-1) - 9*a(n-2).
E.g.f.: 8*exp(x) + 3*exp(9*x). - G. C. Greubel, Nov 12 2019
MAPLE
seq(8+3^(2*n+1), n=0..20); # G. C. Greubel, Nov 12 2019
MATHEMATICA
8 + 3^(2*Range[21]-1) (* G. C. Greubel, Nov 12 2019 *)
PROG
(Sage) [3*9^n+8 for n in [0..20]]
(PARI) a(n)=3*9^n+8 \\ Charles R Greathouse IV, Sep 24 2015
(Magma) [8 + 3^(2*n+1): n in [0..20]]; // G. C. Greubel, Nov 12 2019
(GAP) List([0..20], n-> 8 + 3^(2*n+1)); # G. C. Greubel, Nov 12 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Eric M. Schmidt, Apr 18 2013
STATUS
approved