A177095 9^n - 8.

1, 73, 721, 6553, 59041, 531433, 4782961, 43046713, 387420481, 3486784393, 31381059601, 282429536473, 2541865828321, 22876792454953, 205891132094641, 1853020188851833, 16677181699666561, 150094635296999113

Offset: 1

Author

Vincenzo Librandi, Nov 15 2010

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000
• Index entries for linear recurrences with constant coefficients, signature (10,-9).

Crossrefs

Equals A001019(n)-8.

Programs

Magma

[9^n-8: n in [1..20]];

Mathematica

CoefficientList[Series[(1 + 63 x)/(1 - 10 x + 9 x^2), {x, 0, 30}], x] (* Vincenzo Librandi, Feb 06 2013 *)
LinearRecurrence[{10,-9},{1,73},20] (* Harvey P. Dale, May 22 2014 *)

Formula

G.f.: x*(1 + 63*x)/(1 - 10*x + 9*x^2). - Vincenzo Librandi, Feb 06 2013

a(n) = 10*a(n-1) - 9*a(n-2) for n>2, a(1)=1, a(2)=73. - Vincenzo Librandi, Feb 06 2013