login
A015611
a(n) = 12*a(n-1) + 7*a(n-2).
3
0, 1, 12, 151, 1896, 23809, 298980, 3754423, 47145936, 592032193, 7434407868, 93357119767, 1172326292280, 14721415345729, 184863268194708, 2321409125756599, 29150952386442144, 366061292517601921, 4596792176916318060, 57723935170619030167
OFFSET
0,3
FORMULA
G.f.: x/(1 - 12*x - 7*x^2). - Vincenzo Librandi, Nov 22 2012
MATHEMATICA
Join[{a=0, b=1}, Table[c=12*b+7*a; a=b; b=c, {n, 60}]] (* Vladimir Joseph Stephan Orlovsky, Jan 31 2011 *)
CoefficientList[Series[x/(1 - 12x - 7x^2), {x, 0, 30}], x] (* or *) LinearRecurrence[{12, 7}, {0, 1}, 30] (* Vincenzo Librandi, Nov 22 2012 *)
PROG
(Sage) [lucas_number1(n, 12, -7) for n in range(0, 18)] # Zerinvary Lajos, Apr 29 2009
(Magma) [n le 2 select n-1 else 12*Self(n-1) + 7*Self(n-2): n in [1..30]]; // Vincenzo Librandi, Nov 22 2012
(PARI) x='x+O('x^30); concat([0], Vec(x/(1-12*x-7*x^2))) \\ G. C. Greubel, Dec 30 2017
CROSSREFS
Sequence in context: A053507 A060917 A113358 * A127650 A286432 A189548
KEYWORD
nonn,easy
STATUS
approved