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A006538
Worst cases for Pierce expansions (denominators).
(Formerly M2471)
2
1, 3, 5, 11, 11, 19, 35, 47, 53, 95, 103, 179, 251, 299, 503, 743, 1019, 1319, 1439, 2939, 3359, 3959, 5387, 5387, 5879, 5879, 17747, 17747, 23399, 23399, 23399, 23399, 23399, 23399, 93596, 186479, 186479, 278387, 442679, 493919, 493919, 493919, 830939, 1371719, 1371719, 1371719, 1371719, 1371719, 1371719
OFFSET
1,2
COMMENTS
See A006537 for numerators.
a(58) <= 58017959. - Hiroaki Yamanouchi, Aug 31 2014
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Hiroaki Yamanouchi, Table of n, a(n) for n = 1..57
P. Erdős and Jeffrey Shallit, New bounds on the length of finite Pierce and Engel series, Sem. Theor. Nombres Bordeaux (2) 3 (1991), no. 1, 43-53.
Vlado Kešelj, Length of finite Pierce series: theoretical analysis and numerical computations, Dept. Computer Science, U Waterloo, CS-96-21, Sep 10 1996.
M. E. Mays, Iterating the division algorithm, Fib. Quart., 25 (1987), 204-213.
J. O. Shallit, Metric theory of Pierce expansions, Fibonacci Quart. 24 (1986), pp. 22-40.
FORMULA
Chase & Pandey prove that a(n) >> n^e for some e > 59/19 = 3.105..., improving on Kešelj, Erdős & Shallit, and Shallit. - Charles R Greathouse IV, Jan 14 2023
PROG
(PARI) P(a, b)=my(n); while(b, b=a%b; n++); n
A268058(n)=my(t=1); for(b=2, n-1, t=max(P(n, b), t)); t
a(n, startAt=1)=while(A268058(startAt) < n, startAt++); startAt \\ Charles R Greathouse IV, Jan 14 2023
CROSSREFS
RECORDS transform of A268058.
Sequence in context: A065019 A071328 A273037 * A066281 A072063 A242269
KEYWORD
nonn,frac
EXTENSIONS
Description corrected May 15 1995 and again Nov 07 2006
a(38)-a(49) (from Keselj report) added by R. J. Mathar, Jun 30 2008
STATUS
approved