A199020 a(n) = 4*11^n-1.

3, 43, 483, 5323, 58563, 644203, 7086243, 77948683, 857435523, 9431790763, 103749698403, 1141246682443, 12553713506883, 138090848575723, 1518999334332963, 16708992677662603, 183798919454288643, 2021788113997175083

Offset: 0

Author

Vincenzo Librandi, Nov 02 2011

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..900
• Index entries for linear recurrences with constant coefficients, signature (12,-11).

Programs

Magma

[4*11^n-1 : n in [0..20]];

Mathematica

4*11^Range[0,20]-1 (* or *) LinearRecurrence[{12,-11},{3,43},20] (* Harvey P. Dale, Aug 25 2012 *)
CoefficientList[Series[(3 + 7*x)/(1 - 12*x + 11*x^2), {x, 0, 30}], x] (* Vincenzo Librandi, Jan 04 2013 *)

Formula

a(n) = 11*a(n-1)+10.

a(n) = 12*a(n-1)-11*a(n-2), n>1.

G.f.: (3 + 7*x)/(1 - 12*x + 11*x^2). - Vincenzo Librandi, Jan 04 2013