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A199681
11*9^n+1.
1
12, 100, 892, 8020, 72172, 649540, 5845852, 52612660, 473513932, 4261625380, 38354628412, 345191655700, 3106724901292, 27960524111620, 251644717004572, 2264802453041140, 20383222077370252, 183448998696332260
OFFSET
0,1
FORMULA
a(n) = 9*a(n-1)-8.
a(n) = 10*a(n-1)-9*a(n-2).
G.f.: 4*(3-5*x)/((1-x)*(1-9*x)).
MATHEMATICA
11*9^Range[0, 20]+1 (* or *) LinearRecurrence[{10, -9}, {12, 100}, 20] (* Harvey P. Dale, Apr 26 2017 *)
PROG
(Magma) [11*9^n+1: n in [0..30]];
CROSSREFS
Sequence in context: A016283 A243880 A338811 * A211403 A008547 A109020
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Nov 09 2011
STATUS
approved