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A015575
Expansion of x/(1 - 8*x - 5*x^2).
4
0, 1, 8, 69, 592, 5081, 43608, 374269, 3212192, 27568881, 236612008, 2030740469, 17428983792, 149585572681, 1283829500408, 11018563866669, 94567658435392, 811634086816481, 6965910986708808, 59785458327752869, 513113221555566992, 4403833064083300281, 37796230620444237208
OFFSET
0,3
COMMENTS
Pisano period lengths: 1, 2, 3, 2, 4, 6, 21, 4, 9, 4, 120, 6, 56, 42, 12, 8, 16, 18, 360, 4, ... - R. J. Mathar, Aug 10 2012
FORMULA
a(n) = 8*a(n-1) + 5*a(n-2).
MATHEMATICA
Join[{a=0, b=1}, Table[c=8*b+5*a; a=b; b=c, {n, 100}]] (* Vladimir Joseph Stephan Orlovsky, Jan 17 2011 *)
LinearRecurrence[{8, 5}, {0, 1}, 30] (* Vincenzo Librandi, Nov 14 2012 *)
CoefficientList[Series[x/(1-8x-5x^2), {x, 0, 30}], x] (* Harvey P. Dale, Feb 28 2023 *)
PROG
(Sage) [lucas_number1(n, 8, -5) for n in range(0, 20)] # Zerinvary Lajos, Apr 25 2009
(Magma) [n le 2 select n-1 else 8*Self(n-1) + 5*Self(n-2): n in [1..30]]; // Vincenzo Librandi, Nov 14 2012
(PARI) x='x+O('x^30); concat([0], Vec(x/(1-8*x-5*x^2))) \\ G. C. Greubel, Jan 06 2018
CROSSREFS
Sequence in context: A111156 A297633 A152279 * A214344 A228421 A152109
KEYWORD
nonn,easy
STATUS
approved