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 A159289 a(n+1) = 5*a(n) - 2*a(n-1). 3
 5, 21, 95, 433, 1975, 9009, 41095, 187457, 855095, 3900561, 17792615, 81161953, 370224535, 1688798769, 7703544775, 35140126337, 160293542135, 731187458001, 3335350205735, 15214376112673, 69401180151895, 316577148534129 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS G. C. Greubel, Table of n, a(n) for n = 0..1000 Index entries for linear recurrences with constant coefficients, signature (5, -2). FORMULA From R. J. Mathar, Apr 10 2009: (Start) G.f.: -(-5+4*x)/(1-5*x+2*x^2). a(n) = 5*A107839(n) - 4*A107839(n-1). (End) a(n) = (5/2)*((5/2 + (1/2)*sqrt(17))^n + (5/2 - (1/2)*sqrt(17))^n) + (1/2)*sqrt(17)*((5/2 + (1/2)*sqrt(17))^n - (5/2 - (1/2)*sqrt(17))^n), with n >= 0. - Paolo P. Lava, Jul 31 2009 MATHEMATICA LinearRecurrence[{5, -2}, {5, 21}, 50] (* G. C. Greubel, Jun 27 2018 *) PROG (PARI) x='x+O('x^30); Vec(-(-5+4*x)/(1-5*x+2*x^2)) \\ G. C. Greubel, Jun 27 2018 (Magma) I:=[5, 21]; [n le 2 select I[n] else 5*Self(n-1) - 2*Self(n-2): n in [1..30]]; // G. C. Greubel, Jun 27 2018 CROSSREFS Cf. A107839. Sequence in context: A178876 A202513 A343349 * A201869 A017968 A017969 Adjacent sequences: A159286 A159287 A159288 * A159290 A159291 A159292 KEYWORD nonn,easy AUTHOR Creighton Dement, Apr 08 2009 STATUS approved

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Last modified April 1 06:57 EDT 2023. Contains 361673 sequences. (Running on oeis4.)