OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..900
Index entries for linear recurrences with constant coefficients, signature (14, -13).
FORMULA
E.g.f.: Sum_{d|M} (exp(d*x) - 1)/d, M=13.
From R. J. Mathar, Mar 05 2010: (Start)
a(n) = Sum_{d|13} d^(n-1) = 1 + 13^(n-1) = 1 + A001022(n-1), n > 0.
a(n) = 14*a(n-1) - 13*a(n-2), n > 2.
G.f.: -2*x*(-1+7*x)/((13*x-1)*(x-1)). (End)
a(n) = 13*a(n-1) - 12, n > 1. - Vincenzo Librandi, Sep 17 2011
MATHEMATICA
Join[{0}, 13^(#-1)+1&/@Range[20]] (* or *) Join[{0}, LinearRecurrence[ {14, -13}, {2, 14}, 20]] (* Harvey P. Dale, Oct 14 2013 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
R. J. Mathar, Jul 11 2008
EXTENSIONS
Name changed by Arkadiusz Wesolowski, Sep 08 2013
STATUS
approved