A199112 a(n) = 10*3^n+1.

11, 31, 91, 271, 811, 2431, 7291, 21871, 65611, 196831, 590491, 1771471, 5314411, 15943231, 47829691, 143489071, 430467211, 1291401631, 3874204891, 11622614671, 34867844011, 104603532031, 313810596091, 941431788271, 2824295364811

Offset: 0

Author

Vincenzo Librandi, Nov 04 2011

Keywords

• nonn
• easy

Comments

The inverse binomial transform is 11, 20, 40, 80, 160,... closely related to A020714. - R. J. Mathar, Apr 07 2022

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (4,-3).

Crossrefs

Cf. A020714.

Programs

Magma

[10*3^n+1: n in [0..30]];

Mathematica

10*3^Range[0,30]+1 (* or *) LinearRecurrence[{4,-3},{11,31},30] (* Harvey P. Dale, Dec 07 2011 *)

Formula

a(n) = 3*a(n-1)-2.

a(n) = 4*a(n-1)-3*a(n-2).

G.f.: (11-13*x)/((1-x)*(1-3*x)). - Bruno Berselli, Nov 04 2011