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.

A214070 Decimal expansion of the number whose continued fraction is 1, 2, 4, 8, 16, ...

Original entry on oeis.org

1, 4, 4, 5, 9, 3, 4, 6, 4, 0, 5, 1, 2, 2, 0, 2, 6, 6, 8, 1, 1, 9, 5, 5, 4, 3, 4, 0, 6, 8, 2, 6, 1, 7, 6, 8, 4, 2, 7, 0, 4, 0, 8, 8, 4, 5, 2, 0, 3, 4, 3, 8, 5, 0, 7, 9, 0, 3, 2, 6, 3, 5, 6, 0, 5, 0, 0, 6, 6, 1, 9, 0, 0, 6, 9, 1, 6, 2, 3, 2, 7, 7, 8, 9, 9, 7, 7, 7, 1, 6, 1, 8, 9, 0, 3, 9, 9, 2, 1, 4, 6, 2, 0, 4, 2
Offset: 1

Views

Author

Robert G. Wilson v, Aug 06 2012

Keywords

Comments

Essentially the same as A096641. - R. J. Mathar, Aug 10 2012

Examples

			1.4459346405122026681195543406826176842704088452034385079032635605006619006916...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[ FromContinuedFraction[{1, 2^Range@ 19}], 10, 111][[1]]

Formula

From Amiram Eldar, Feb 08 2022: (Start)
Equals A096641 + 1.
Equals 1/A275614. (End)

A096641 Decimal expansion of number with continued fraction expansion 0, 2, 4, 8, 16, ... (0 and positive powers of 2).

Original entry on oeis.org

4, 4, 5, 9, 3, 4, 6, 4, 0, 5, 1, 2, 2, 0, 2, 6, 6, 8, 1, 1, 9, 5, 5, 4, 3, 4, 0, 6, 8, 2, 6, 1, 7, 6, 8, 4, 2, 7, 0, 4, 0, 8, 8, 4, 5, 2, 0, 3, 4, 3, 8, 5, 0, 7, 9, 0, 3, 2, 6, 3, 5, 6, 0, 5, 0, 0, 6, 6, 1, 9, 0, 0, 6, 9, 1, 6, 2, 3, 2, 7, 7, 8, 9, 9, 7, 7, 7, 1, 6, 1, 8, 9, 0, 3, 9, 9, 2, 1, 4, 6, 2, 0, 4, 2, 4
Offset: 0

Views

Author

Rick L. Shepherd, Jun 30 2004

Keywords

Comments

According to the Mc Laughlin-Wyshinski paper, Tasoev proposed continued fractions of the form [a0;a,...,a,a^2,...,a^2,a^3,...,a^3,...], where a0 >= 0, a >= 2 and m >= 1 are integers and each power of a occurs m times. This sequence is for the minimal values a0 = 0, a = 2 and m = 1. Komatsu "derived a closed form for the general case (m >= 1, arbitrary)" and the expression given in (1.2) (where a0=0 and m=1) of the linked paper and which is used in the second PARI/GP program below.

Examples

			0.445934640512202668119554340682617684270408845203438507903263560500661900...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[FromContinuedFraction[{0, 2^Range@ 19}], 10, 111][[1]] (* Robert G. Wilson v, Jan 04 2013 *)
  • PARI
    \p 400
    dec_exp(v)= w=contfracpnqn(v); w[1,1]/w[2,1]+0.
    dec_exp(vector(400,i,if(i==1,0,2^(i-1))))
    /* The following uses Komatsu's expression for given a; a0=0, m=1 */
    {Komatsu(a)=suminf(s=0,a^(-(s+1)^2)*prod(i=1,s,(a^(2*i)-1)^(-1))) /suminf(s=0,a^(-s^2)*prod(i=1,s,(a^(2*i)-1)^(-1)))}
    Komatsu(2) /* generates this sequence's constant */

Formula

From Amiram Eldar, Feb 08 2022: (Start)
Equals A214070 - 1.
Equals 1/A275614 - 1. (End)
Showing 1-2 of 2 results.