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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A050170 a(1) = 1, a(n) = floor(a(n-1)/sqrt(5)) if this is not among 0,a(1),...,a(n-1); otherwise a(n) = floor(a(n-1))*sqrt(5)). 5
1, 2, 4, 8, 3, 6, 13, 5, 11, 24, 10, 22, 9, 20, 44, 19, 42, 18, 40, 17, 7, 15, 33, 14, 31, 69, 30, 67, 29, 12, 26, 58, 25, 55, 122, 54, 120, 53, 23, 51, 114, 50, 111, 49, 21, 46, 102, 45, 100, 223, 99, 221, 98, 43, 96, 214, 95, 212, 94, 210 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Does every positive integer occur exactly once?

Records occur at indices 1, 2, 3, 4, 7, 10, 15, 26, 35, 50, 87, 124, 179, 306, ... with corresponding values 1, 2, 4, 8, 13, 24, 44, 69, 122, 223, 348, 614, 1118, 1744, .... - Peter Kagey, Jan 24 2018

LINKS

Ivan Neretin, Table of n, a(n) for n = 1..10000

MATHEMATICA

a[1] = 1; a[n_] := a[n] = If[FreeQ[Join[{0}, Array[a, n-1]], f = Floor[a[n-1]/Sqrt[5]]], f, Floor[a[n-1]*Sqrt[5]]]; Array[a, 60] (* Jean-Fran├žois Alcover, Sep 12 2017 *)

CROSSREFS

Sequence in context: A036118 A247555 A101942 * A087089 A197382 A246363

Adjacent sequences:  A050167 A050168 A050169 * A050171 A050172 A050173

KEYWORD

nonn,look

AUTHOR

Clark Kimberling

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 21 20:22 EST 2020. Contains 332111 sequences. (Running on oeis4.)