The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A105397 Periodic with period 2: repeat [4,2]. 11
 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2, 4, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS A simple "Fractal Jump Sequence" (FJS).  An FJS is a sequence of digits containing an infinite number of copies of itself. Modus operandi: underline the first digit "a" of such a sequence then jump over the next "a" digits and underline the digit "b" on which you land. Jump from there over the next "b" digits and underline the digit "c" on which you land. Etc. The "abc...n..." succession of underlined digits is the sequence itself. Simple continued fraction of 2+sqrt(6). - R. J. Mathar, Nov 21 2011 LINKS Index entries for linear recurrences with constant coefficients, signature (0,1). FORMULA a(n) = 3 + (-1)^n = 4 - 2*(n mod 2) = 2 * 2^((n+1) mod 2). - Wesley Ivan Hurt, Mar 14 2014 MAPLE A105397:=n->3 + (-1)^n; seq(A105397(n), n=0..100); # Wesley Ivan Hurt, Mar 14 2014 MATHEMATICA Table[3 + (-1)^n, {n, 0, 100}] (* Wesley Ivan Hurt, Mar 14 2014 *) LinearRecurrence[{0, 1}, {4, 2}, 75] (* Ray Chandler, Aug 25 2015 *) PROG (PARI) contfrac(2+sqrt(6)) \\ Michel Marcus, Mar 18 2014 CROSSREFS Cf. A010694 (period 2, repeat [2,4]). First differences of A007310. - Fred Daniel Kline, Aug 17 2020 Sequence in context: A064127 A178253 A209272 * A328999 A236185 A300004 Adjacent sequences:  A105394 A105395 A105396 * A105398 A105399 A105400 KEYWORD easy,nonn AUTHOR Eric Angelini, May 01 2005 EXTENSIONS Edited by N. J. A. Sloane, Jun 08 2010 STATUS approved

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

Last modified January 20 04:53 EST 2021. Contains 340301 sequences. (Running on oeis4.)