A015601 a(n) = 11*a(n-1) + 7*a(n-2).

0, 1, 11, 128, 1485, 17231, 199936, 2319913, 26918595, 312343936, 3624213461, 42052755623, 487949806080, 5661817156241, 65695637361211, 762284731067008, 8845001503265565, 102631009653390271, 1190856116710151936, 13817834351385403193

Offset

0,3

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..900

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

Formula

a(n) = -(1/149)*(11/2 - (1/2)*sqrt(149))^n*sqrt(149) + (1/149)*(11/2 + (1/2)*sqrt(149))^n*sqrt(149). - Paolo P. Lava, Jul 09 2008

G.f.: x/(1-11*x-7*x^2). - Zerinvary Lajos, Apr 27 2009

Mathematica

Join[{a=0, b=1}, Table[c=11*b+7*a; a=b; b=c, {n, 60}]] (* Vladimir Joseph Stephan Orlovsky, Jan 31 2011 *)
LinearRecurrence[{11, 7}, {0, 1}, 30] (* Vincenzo Librandi, Nov 22 2012 *)

Prog

(Sage) [lucas_number1(n, 11, -7) for n in range(0, 18)] # Zerinvary Lajos, Apr 27 2009
(Magma) [n le 1 select n else 11*Self(n)+7*Self(n-1): n in [0..30]]; // Vincenzo Librandi, Nov 22 2012

Crossrefs

Sequence in context: A181012 A168327 A282042 * A024144 A201877 A015602

Adjacent sequences: A015598 A015599 A015600 * A015602 A015603 A015604

Keyword

nonn,easy

Author

Olivier Gérard

Status

approved