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 A081075 a(n) = Fibonacci(4n+2) - 3. 0
 5, 52, 374, 2581, 17708, 121390, 832037, 5702884, 39088166, 267914293, 1836311900, 12586269022, 86267571269, 591286729876, 4052739537878, 27777890035285, 190392490709132, 1304969544928654, 8944394323791461 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES Hugh C. Williams, Edouard Lucas and Primality Testing, John Wiley and Sons, 1998, p. 75. LINKS Index entries for linear recurrences with constant coefficients, signature (8,-8,1). FORMULA a(n) = 8*a(n-1) - 8*a(n-2) + a(n-3). a(n) = -3 + 4*((7/2 - (3/2)*sqrt(5))^n + (7/2 + (3/2)*sqrt(5))^n) + (9/5)*sqrt(5) ((7/2 + (3/2)*sqrt(5))^n - (7/2 - (3/2)*sqrt(5))^n). - Paolo P. Lava, Dec 01 2008 G.f.: x*(2*x^2-12*x-5)/((x-1)*(x^2-7*x+1)). - Colin Barker, Jun 22 2012 a(n) = Fibonacci(2*n+3)*Lucas(2*n-1). - Ehren Metcalfe, Apr 21 2019 MAPLE with(combinat): for n from 1 to 40 do printf(`%d, `, fibonacci(4*n+2)-3) od: # James A. Sellers, Mar 05 2003 MATHEMATICA Array[Fibonacci[4 # + 2] - 3 &, 19] (* Michael De Vlieger, Apr 21 2019 *) PROG (MAGMA) [Fibonacci(4*n+2)-3: n in [1..50]]; // Vincenzo Librandi, Apr 20 2011 CROSSREFS Cf. A000045 (Fibonacci numbers), A000032 (Lucas numbers). Sequence in context: A045539 A281202 A173719 * A247766 A247777 A193809 Adjacent sequences:  A081072 A081073 A081074 * A081076 A081077 A081078 KEYWORD nonn,easy AUTHOR R. K. Guy, Mar 04 2003 EXTENSIONS More terms from James A. Sellers, Mar 05 2003 STATUS approved

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Last modified April 18 19:31 EDT 2021. Contains 343089 sequences. (Running on oeis4.)