A132805 A trisection of A024495.

0, 3, 21, 171, 1365, 10923, 87381, 699051, 5592405, 44739243, 357913941, 2863311531, 22906492245, 183251937963, 1466015503701, 11728124029611, 93824992236885, 750599937895083, 6004799503160661, 48038396025285291, 384307168202282325, 3074457345618258603

Offset: 0

Author

Paul Curtz, Nov 18 2007

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..1000
• Index entries for linear recurrences with constant coefficients, signature (7,8).

Crossrefs

Cf. A029898.

Programs

Magma

[-(1/3)*(-1)^n+(1/3)*8^n: n in [0..25]]; // Vincenzo Librandi, Aug 10 2011

Mathematica

LinearRecurrence[{7,8},{0,3},40] (* Harvey P. Dale, Feb 08 2015 *)

Formula

From Philippe Deléham, Nov 19 2007: (Start)

a(n) = A132804(n)/2.

G.f.: 3x/(1 - 7*x - 8*x^2).

a(n+1) = 7*a(n) + 8*a(n-1) for n >= 1, a(0)=0, a(1)=3. (End)

a(n) = 3*A015565(n). - R. J. Mathar, Aug 07 2017