cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A038705 Position of the incrementally largest term in continued fraction for Champernowne constant (A030167).

Original entry on oeis.org

1, 2, 3, 5, 19, 41, 163, 527, 1709, 4839, 13523, 34063
Offset: 1

Views

Author

Hans Havermann, May 01 2000

Keywords

Crossrefs

See A143533 for another version.
Cf. A143532 (number of decimal digits in n-th term of c.f.).
Cf. A143534 (number of decimal digits in a(n)-th term of c.f.).

Extensions

a(10) = 13523 (from Mark Sofroniou) contributed by Eric W. Weisstein, Sep 04 2008.
Edited by N. J. A. Sloane, Apr 03 2010.
a(11) = 34063 contributed by John K. Sikora, Aug 24 2012.

A143534 Number of decimal digits in the high-water marks of the terms of the continued fraction of the (base-10) Champernowne constant.

Original entry on oeis.org

0, 1, 1, 6, 166, 2504, 33102, 411100, 4911098, 57111096, 651111094, 7311111092
Offset: 1

Views

Author

Eric W. Weisstein, Aug 22 2008

Keywords

Crossrefs

Cf. A038705 (position of the incrementally largest term in continued fraction for Champernowne constant).
Cf. A143533 (another version of A038705).

Programs

  • Ruby
    puts (4..13).collect {|n| (1..(n-3)).inject(0) {|sum, m| sum+9*m*10**(m-1)}+3-n-2*((1..(n-4)).inject(0) {|sum1, m1| sum1+9*m1*10**(m1-1)}+3-(n-1))-3*(n-2)+4} # John K. Sikora, Aug 25 2012

Formula

It appears that: For N>=3, define NCD(N)=3-N+(sum{m=1..(N-3), m>0} 9*m*10^(m-1)); then for n>=4, a(n) = NCD(n) - 2*NCD(n-1) - 3*(n-2) + 4. - John K. Sikora, Aug 25 2012

Extensions

a(11) = 651111094 (from Mark Sofroniou), Eric W. Weisstein, Sep 04 2008
a(12) = 7311111092 from Eric W. Weisstein, Jun 29 2013
Showing 1-2 of 2 results.