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.

A002285 Decimal expansion of common logarithm of e.

Original entry on oeis.org

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

Views

Author

Keywords

Comments

Sometimes also called Briggs's constant after the English mathematician Henry Briggs (1561-1630). - Martin Renner, Jan 03 2022

Examples

			0.4342944819...
		

References

  • M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 2.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
  • Jerome Spanier and Keith B. Oldham, "Atlas of Functions", Hemisphere Publishing Corp., 1987, chapter 25, equations 25:14:4 at page 232.
  • David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, Revised edition 1987, p. 27.

Crossrefs

Programs

Formula

Equals log_10(e) = 1/log(10) = 1/A002392. - Eric Desbiaux, Jun 27 2009
Conjecture by Eric Weisstein: Equals lim_{n->oo} b(n)/10^(n-1), for b=A114467 or b=A114468 (i.e., is the limit of the decimal expansion of the number of decimal digits in both the numerator and denominator of the (10^n)th harmonic number). More generally, log_k(e) seems to equal lim_{n->oo} floor(log_k(b(k^n)))/k^(n-1), for b=A001008 or b=A002805 and k >= 2. - Natalia L. Skirrow, Feb 12 2023

A114467 Number of decimal digits in the numerator of the 10^n-th harmonic number.

Original entry on oeis.org

1, 4, 41, 434, 4346, 43451, 434111, 4342303, 43428680
Offset: 0

Views

Author

Eric W. Weisstein, Nov 29 2005

Keywords

Comments

See A114468 for denominators.
Eric Weisstein's link conjectures that for both this sequence and A114468, a(n) ~ (log_10(e) = A002285)*10^n. - Natalia L. Skirrow, Jun 22 2023

Crossrefs

Programs

  • Mathematica
    Table[IntegerLength[Numerator[HarmonicNumber[10^n]]],{n,0,8}](* Harvey P. Dale, May 24 2019 *)
  • Python
    from gmpy2 import digits, mpq
    def a(n): return len(digits(sum(mpq(1, n) for n in range(1, 10**n+1)).numerator))
    print([a(n) for n in range(6)]) # Michael S. Branicky, Jun 22 2023

Extensions

Edited by Charles R Greathouse IV, Aug 05 2010
Showing 1-2 of 2 results.