OFFSET
0,1
COMMENTS
Number of conjugacy classes in Ree group 2F4(2*4^n).
LINKS
Eric M. Schmidt, Table of n, a(n) for n = 0..500
Frank Luebeck, Numbers of Conjugacy Classes in Finite Groups of Lie Type.
Index entries for linear recurrences with constant coefficients, signature (21,-84,64).
FORMULA
G.f.: 17/(1-x) + 8/(1-4x) + 4/(1-16x).
a(n) = 21*a(n-1) - 84*a(n-2) + 64*a(n-3) for n > 2. - Wesley Ivan Hurt, Oct 08 2017
MATHEMATICA
LinearRecurrence[{21, -84, 64}, {29, 113, 1169}, 20] (* Harvey P. Dale, May 06 2016 *)
PROG
(Sage) [4*16^n + 8*4^n + 17 for n in [0..20]]
(PARI) a(n)=4*16^n+8*4^n+17 \\ Charles R Greathouse IV, May 22 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Eric M. Schmidt, May 21 2013
STATUS
approved