OFFSET
1,1
LINKS
Harry J. Smith, Table of n, a(n) for n = 1..200
Index entries for linear recurrences with constant coefficients, signature (12, -27).
FORMULA
a(n) = 3^(n-1) * (3^n + 2).
From Chai Wah Wu, Jun 10 2020: (Start)
a(n) = 12*a(n-1) - 27*a(n-2) for n > 2.
G.f.: x*(5 - 27*x)/((3*x - 1)*(9*x - 1)). (End)
EXAMPLE
a(1) = 5 because the character table of C_3 is / 1, 1, 1 / 1, z, z^2 / 1, z^2, z / where z = e^(2 * Pi * i /3) is a primitive cube root of unity.
PROG
(PARI) { for (n=1, 200, write("b061253.txt", n, " ", 3^(n-1) * (3^n + 2)) ) } \\ Harry J. Smith, Jul 20 2009
CROSSREFS
KEYWORD
nonn
AUTHOR
Ahmed Fares (ahmedfares(AT)my-deja.com), Jun 02 2001
EXTENSIONS
More terms from Harry J. Smith, Jul 20 2009
STATUS
approved