

A050170


a(1) = 1, a(n) = floor(a(n1)/sqrt(5)) if this is not among 0,a(1),...,a(n1); otherwise a(n) = floor(a(n1))*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
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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, n1]], f = Floor[a[n1]/Sqrt[5]]], f, Floor[a[n1]*Sqrt[5]]]; Array[a, 60] (* JeanFrançois 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



