A015570 Expansion of x/(1 - 7*x - 11*x^2).

0, 1, 7, 60, 497, 4139, 34440, 286609, 2385103, 19848420, 165175073, 1374558131, 11438832720, 95191968481, 792170939287, 6592308228300, 54860037930257, 456535656023099, 3799210009394520, 31616362282015729, 263105846077449823, 2189520907644321780, 18220810660362200513

Offset

0,3

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (7,11).

Formula

a(n) = 7*a(n-1) + 11*a(n-2).

Mathematica

a[n_]:=(MatrixPower[{{1, 3}, {1, -8}}, n].{{1}, {1}})[[2, 1]]; Table[Abs[a[n]], {n, -1, 40}] (* Vladimir Joseph Stephan Orlovsky, Feb 19 2010 *)
LinearRecurrence[{7, 11}, {0, 1}, 30] (* Vincenzo Librandi, Nov 14 2012 *)

Prog

(Sage) [lucas_number1(n, 7, -11) for n in range(0, 20)] # Zerinvary Lajos, Apr 24 2009
(Magma) [n le 2 select n-1 else 7*Self(n-1) + 11*Self(n-2): n in [1..30]]; // Vincenzo Librandi, Nov 14 2012
(PARI) x='x+O('x^30); concat([0], Vec(x/(1-7*x-11*x^2))) \\ G. C. Greubel, Jan 06 2018

Crossrefs

Sequence in context: A063969 A366613 A303120 * A290756 A024090 A241770

Adjacent sequences: A015567 A015568 A015569 * A015571 A015572 A015573

Keyword

nonn,easy

Author

Olivier Gérard

Status

approved