OFFSET
0,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (10,-9).
FORMULA
a(n) = 9*a(n-1)-2.
a(n) = 10*a(n-1)-9*a(n-2).
G.f.: (3-5*x)/((1-x)*(1-9*x)).
MATHEMATICA
(11 9^Range[0, 20]+1)/4 (* or *) LinearRecurrence[{10, -9}, {3, 25}, 20] (* Harvey P. Dale, Apr 29 2019 *)
PROG
(Magma) [(11*9^n+1)/4: n in [0..30]];
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Nov 09 2011
STATUS
approved