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A023183 a(n) = least k such that Fibonacci(k) ends with n, or -1 if there are none. 5
0, 1, 3, 4, 9, 5, 21, 14, 6, 11, 15, 22, 216, 7, 111, 130, 168, 37, 27, 112, 60, 8, 117, 64, 198, 25, 99, 136, 204, 29, 105, 88, 174, 13, 9, 70, 222, 43, 93, 172, 30, 41, 63, 124, 12, 55, 21, 154, 186, 49, 75, 148, 36, 67, 129, 10, 162, 23, 87, 118, 180, 61, 57, 166, 72, 20 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

It appears that if n is greater than 99 and congruent to 4 or 6 (mod 8) then there is no Fibonacci number ending in that n. - Jason Earls, Jun 19 2004

This is because there is no Fibonacci number == 4 or 6 (mod 8). - Robert Israel, Sep 11 2020

LINKS

Robert Israel, Table of n, a(n) for n = 0..9999

MAPLE

V:= Array(0..999, -1):

V[0]:= 0: u:= 1: v:= 0:

for n from 1 to 1500 do

  t:= v;

  v:= u+v mod 1000;

  u:= t;

  if V[v] = -1 then V[v]:= n fi;

  if V[v mod 100] = -1 then V[v mod 100] := n fi;

  if V[v mod 10] = -1 then V[v mod 10]:= n fi;

od:

seq(V[i], i=0..999); # Robert Israel, Sep 11 2020

MATHEMATICA

d[n_]:=IntegerDigits[n]; Table[j=0; While[Length[d[Fibonacci[j]]]<(le=Length[y=d[n]]), j++]; i=j; While[Take[d[Fibonacci[i]], -le]!=y, i++]; i, {n, 0, 65}] (* Jayanta Basu, May 18 2013 *)

CROSSREFS

Cf. A000045, A023184, A020344, A020345.

Sequence in context: A256469 A192334 A140439 * A102320 A227717 A021290

Adjacent sequences:  A023180 A023181 A023182 * A023184 A023185 A023186

KEYWORD

sign,base,look

AUTHOR

David W. Wilson

STATUS

approved

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Last modified December 7 03:52 EST 2021. Contains 349567 sequences. (Running on oeis4.)