A253213 a(n) = 10^n + 9.

10, 19, 109, 1009, 10009, 100009, 1000009, 10000009, 100000009, 1000000009, 10000000009, 100000000009, 1000000000009, 10000000000009, 100000000000009, 1000000000000009, 10000000000000009, 100000000000000009, 1000000000000000009, 10000000000000000009

Offset

0,1

Links

Table of n, a(n) for n=0..19.

Index entries for linear recurrences with constant coefficients, signature (11,-10).

Formula

a(n) = 11*a(n-1) - 10*a(n-2) for n>1.

G.f.: (10 - 91*x)/((1 - x)*(1 - 10*x)).

Mathematica

Table[10^n + 9, {n, 0, 40}]
LinearRecurrence[{11, -10}, {10, 19}, 40] (* Harvey P. Dale, Jun 29 2018 *)

Prog

(Magma) [10^n+9: n in [0..30]];

Crossrefs

Cf. similar sequences listed in A253208.

Cf. A170955.

Sequence in context: A070199 A015445 A220005 * A293929 A177203 A177167

Adjacent sequences: A253210 A253211 A253212 * A253214 A253215 A253216

Keyword

nonn,easy

Author

Vincenzo Librandi, Dec 30 2014

Status

approved