The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A065530 If n is odd then a(n) = n, else a(n) = n*(n+2). 3
 0, 1, 8, 3, 24, 5, 48, 7, 80, 9, 120, 11, 168, 13, 224, 15, 288, 17, 360, 19, 440, 21, 528, 23, 624, 25, 728, 27, 840, 29, 960, 31, 1088, 33, 1224, 35, 1368, 37, 1520, 39, 1680, 41, 1848, 43, 2024, 45, 2208, 47, 2400, 49, 2600, 51, 2808, 53, 3024, 55, 3248, 57 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Order of Fibonacci group F(n+1,2) (0 means group is infinite). - N. J. A. Sloane, Dec 30 2011 REFERENCES D. L. Johnson, Presentation of Groups, Cambridge, 1976, p. 182. Thomas, Richard M., The Fibonacci groups revisited, in Groups - St. Andrews 1989, Vol. 2, 445-454, London Math. Soc. Lecture Note Ser., 160, Cambridge Univ. Press, Cambridge, 1991. LINKS Harry J. Smith, Table of n, a(n) for n = 0..1000 Index entries for linear recurrences with constant coefficients, signature (0,3,0,-3,0,1). FORMULA O.g.f.: (x+8x^2-x^5)/(1-x^2)^3. - Len Smiley, Dec 04 2001 a(n) = 3*a(n-2)-3*a(n-4)+a(n-6) for n>5. - Colin Barker, May 02 2015 MATHEMATICA Array[If[OddQ[#], #, #*(#+2)] &, 100, 0] (* Paolo Xausa, Feb 22 2024 *) PROG (PARI) { for (n=0, 1000, if (n%2, a=n, a=n*(n + 2)); write("b065530.txt", n, " ", a) ) } \\ Harry J. Smith, Oct 20 2009 (PARI) concat(0, Vec(x*(x^4-8*x-1)/((x-1)^3*(x+1)^3) + O(x^100))) \\ Colin Barker, May 02 2015 CROSSREFS A column of A202624. Sequence in context: A228691 A228313 A037206 * A137481 A228886 A182160 Adjacent sequences: A065527 A065528 A065529 * A065531 A065532 A065533 KEYWORD easy,nonn AUTHOR George E. Antoniou, Dec 02 2001 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 25 07:15 EDT 2024. Contains 372782 sequences. (Running on oeis4.)