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A199687
7*10^n+1.
2
8, 71, 701, 7001, 70001, 700001, 7000001, 70000001, 700000001, 7000000001, 70000000001, 700000000001, 7000000000001, 70000000000001, 700000000000001, 7000000000000001, 70000000000000001, 700000000000000001, 7000000000000000001
OFFSET
0,1
FORMULA
a(n) = 10*a(n-1)-9.
a(n) = 11*a(n-1)-10*a(n-2).
G.f.: (8-17*x)/((1-x)*(1-10*x)).
MATHEMATICA
7*10^Range[0, 20]+1 (* or *) LinearRecurrence[{11, -10}, {8, 71}, 20] (* Harvey P. Dale, May 29 2018 *)
PROG
(Magma) [7*10^n+1: n in [0..30]];
CROSSREFS
Sequence in context: A152265 A081178 A096341 * A225033 A075506 A334670
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Nov 09 2011
STATUS
approved