

A057167


Term in Recamán's sequence A005132 where n appears for first time, or 1 if n never appears.


20



0, 1, 4, 2, 131, 129, 3, 5, 16, 14, 12, 10, 8, 6, 31, 29, 27, 25, 23, 99734, 7, 9, 11, 13, 15, 17, 64, 62, 60, 58, 56, 54, 52, 50, 48, 46, 44, 42, 40, 38, 111, 22, 20, 18, 28, 30, 32, 222, 220, 218, 216, 214, 212, 210, 208, 206, 204, 202, 200, 198, 196
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OFFSET

0,3


LINKS

T. D. Noe, Table of n, a(n) for n=0..1642 (taking a(1355) from A064227)
Nick Hobson, Python program for this sequence
C. L. Mallows, Plot (jpeg) of first 10000 terms of A005132
C. L. Mallows, Plot (postscript) of first 10000 terms of A005132
N. J. A. Sloane, My favorite integer sequences, in Sequences and their Applications (Proceedings of SETA '98).
N. J. A. Sloane, FORTRAN program for A005132, A057167, A064227, A064228
Index entries for sequences related to Recamán's sequence


MAPLE

w := array(1..10000); for j from 1 to 100 do l := 0; for k from 1 to nops(a) do if a[k] = j then l := k; exit; fi; od: w[j] := l; od: s := [seq(w[j], j=1..100)]; # where a is an array formed from sequence A005132


MATHEMATICA

A005132 = {0}; Do[If[(r = Last[A005132]  n) <= 0  MemberQ[ A005132, r], r = r + 2n]; AppendTo[ A005132, r], {n, 1, 10^5}]; a[n_] := If[p = Position[ A005132, n]; p == {}, 0, p[[1, 1]]  1]; Table[a[n], {n, 1, 60}] (* JeanFrançois Alcover, Jul 18 2012 *)


CROSSREFS

Cf. A005132, A057165, A057166.
Cf. also A187943, A187922.
Sequence in context: A201228 A010319 A266069 * A096683 A158903 A273148
Adjacent sequences: A057164 A057165 A057166 * A057168 A057169 A057170


KEYWORD

nonn,easy,nice,look


AUTHOR

N. J. A. Sloane, Sep 14 2000


EXTENSIONS

I conjecture a(n) is never 1  but see A064227, A064228.
a(0)=0 added and escape clause value changed to 1 by N. J. A. Sloane, May 01 2020


STATUS

approved



