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A107480 a(n) = a(n-1) + a(n-3) + a(n-4) + a(n-5) + a(n-7). 10
0, 1, 1, 2, 3, 5, 8, 14, 25, 42, 71, 121, 207, 353, 601, 1025, 1748, 2980, 5080, 8661, 14767, 25176, 42922, 73178, 124762, 212707, 362644, 618273, 1054096, 1797131, 3063933, 5223708, 8905915, 15183719, 25886764, 44134416, 75244889, 128285220, 218713827 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
COMMENTS
Lim_{n->infinity} a(n)/a(n-1) = 1.70490277..., the real root of x^5 = x^4 + x^3 + 1.
LINKS
Peter Borwein and Kevin G. Hare, Some computations on Pisot and Salem numbers, 2000, table 1, p. 7.
Peter Borwein and Kevin G. Hare, Some computations on the spectra of Pisot and Salem numbers, Math. Comp. 71 (2002), 767-780.
FORMULA
G.f.: x*(1 + x^2 - x^5) / ((1 + x^2)*(1 - x - x^2 - x^5)). - Colin Barker, Dec 17 2017
MATHEMATICA
LinearRecurrence[{1, 0, 1, 1, 1, 0, 1}, {0, 1, 1, 2, 3, 5, 8}, 50] (* Harvey P. Dale, May 21 2012 *)
PROG
(PARI) concat([0], Vec(x*(1 + x^2 - x^5) / ((1 + x^2)*(1 - x - x^2 - x^5)) + O(x^40))) \\ Colin Barker, Dec 17 2017
(Magma) m:=40; R<x>:=PowerSeriesRing(Integers(), m); [0] cat Coefficients(R!(x*(1 +x^2-x^5)/((1+x^2)*(1-x-x^2-x^5)))); // G. C. Greubel, Nov 03 2018
CROSSREFS
Cf. A013984.
Sequence in context: A290075 A104882 A091956 * A345235 A128021 A036241
KEYWORD
nonn,easy,less
AUTHOR
Roger L. Bagula, May 27 2005
EXTENSIONS
Entry rewritten by Charles R Greathouse IV, Jan 26 2011
STATUS
approved

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Last modified April 23 05:56 EDT 2024. Contains 371906 sequences. (Running on oeis4.)