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 1-4 of 4 results.

A080130 Decimal expansion of exp(-gamma).

Original entry on oeis.org

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

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Author

Benoit Cloitre, Jan 26 2003

Keywords

Comments

By Mertens's third theorem, lim_{k->oo} (H_{k-1}*Product_{prime p<=k} (1-1/p)) = exp(-gamma), where H_n is the n-th harmonic number. Let F(x) = lim_{n->oo} ((Sum_{k<=n} 1/k^x)*(Product_{prime p<=n} (1-1/p^x))) for real x in the interval 0 < x < 1. Consider the function F(s) of the complex variable s, but without the analytic continuation of the zeta function, in the critical strip 0 < Re(s) < 1. - Thomas Ordowski, Jan 26 2023

Examples

			0.56145948356688516982414321479088078676571...
		

References

  • Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Sections 1.5 p. 29, 2.7 p. 117 and 5.4 p. 285.

Crossrefs

Programs

  • Magma
    R:= RealField(100); Exp(-EulerGamma(R)); // G. C. Greubel, Aug 28 2018
  • Maple
    evalf(exp(-gamma), 120);  # Alois P. Heinz, Feb 24 2022
  • Mathematica
    RealDigits[N[Exp[-EulerGamma], 200]][[1]] (* Arkadiusz Wesolowski, Aug 26 2012 *)
  • PARI
    default(realprecision, 100); exp(-Euler) \\ G. C. Greubel, Aug 28 2018
    

Formula

Equals lim inf_{n->oo} phi(n)*log(log(n))/n. - Arkadiusz Wesolowski, Aug 26 2012
From Alois P. Heinz, Dec 05 2018: (Start)
Equals lim_{n->oo} A322364(n)/(n*A322365(n)).
Equals lim_{n->oo} A322380(n)/A322381(n). (End)
Equals lim_{k->oo} log(k)*Product_{prime p<=k} (1-1/p). - Amiram Eldar, Jul 09 2020
Equals lim_{n->oo} A007838(n)/A000142(n). - Alois P. Heinz, Feb 24 2022
Equals Product_{k>=1} (1+1/k)*exp(-1/k). - Amiram Eldar, Mar 20 2022
Equals A001113^(-A001620). - Omar E. Pol, Dec 14 2022
Equals lim_{n->oo} (A001008(p_n-1)/A002805(p_n-1))*(A038110(n+1)/A060753(n+1)), where p_n = A000040(n). - Thomas Ordowski, Jan 26 2023

A094644 Continued fraction for e^gamma.

Original entry on oeis.org

1, 1, 3, 1, 1, 3, 5, 4, 1, 1, 2, 2, 1, 7, 9, 1, 16, 1, 1, 1, 2, 6, 1, 2, 1, 6, 2, 59, 1, 1, 1, 3, 3, 3, 2, 1, 3, 5, 100, 1, 58, 1, 2, 1, 94, 1, 1, 2, 2, 10, 1, 2, 7, 1, 3, 4, 5, 3, 10, 1, 21, 1, 11, 1, 4, 1, 2, 2, 1, 2, 2, 1, 8, 3, 2, 1, 1, 6, 1, 2, 2, 1, 38, 2, 1, 4, 1, 3, 1, 1, 5, 3, 1, 52, 1, 2, 2, 1, 1
Offset: 0

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Author

Keywords

Comments

Increasing partial quotients are: 1,3,5,7,9,16,59,100,129,314,2294,1568705
e^gamma appears in theorems of Mertens, Gronwall, Ramanujan, and Robin on primes, the sum-of-divisors function, and the Riemann Hypothesis (see Caveney-Nicolas-Sondow 2011, pp. 1-2).

Examples

			1 + 1/(1 + 1/(3 + 1/(1 + 1/(1 + 1/(3 + 1/(5 + 1/(4 + ...)))))))
		

References

  • J. Havil, Gamma, Exploring Euler's Constant, Princeton University Press, Princeton and Oxford, 2003, page 97.
  • G. Boros and V. Moll, Irresistible Integrals: Symbolics, Analysis and Experiments in the Evaluation of Integrals, Cambridge University Press, Cambridge, 2004, Chap. 10.

Crossrefs

Cf. A073004 = decimal expansion of exp(gamma).
Gamma is the Euler-Mascheroni constant A001620.
Cf. A079650 = continued fraction for exp(-gamma). [From R. J. Mathar, Sep 05 2008]

Programs

  • Mathematica
    ContinuedFraction[ Exp[ EulerGamma], 100]
  • PARI
    contfrac(exp(Euler)) \\ Amiram Eldar, Jun 13 2021

Extensions

Offset changed by Andrew Howroyd, Aug 07 2024

A179950 Continued fraction for gamma^e, where gamma is the Euler-Mascheroni constant.

Original entry on oeis.org

0, 4, 2, 4, 1, 14, 2, 1, 4, 1, 19, 3, 1, 4, 10, 13, 1, 5, 67, 3, 1, 3, 1, 1, 1, 1, 3, 11, 1, 1, 5, 4, 3, 3, 1, 16, 1, 1, 1, 2, 3, 5, 1, 1, 41, 1, 1, 4, 17, 3, 24, 1, 7, 307, 8, 1, 1, 2, 1, 2, 3, 2, 3, 4, 1, 2, 3, 1, 1, 21, 3, 17, 2, 5, 5, 1, 1, 2, 1, 2, 915, 1, 1, 2, 4, 1, 1, 1, 3, 1, 19, 54, 3, 1, 9, 8
Offset: 0

Views

Author

Michel Lagneau, Aug 03 2010

Keywords

Examples

			gamma^e =.224517251983232062665128293743... = 0 + 1/(4 + 1/(2 + 1/(4 + 1/(1 + ...))))
		

Crossrefs

Cf. A001620 (gamma), A073018 (decimal expansion).

Programs

  • Maple
    with(numtheory): Digits := 300: convert(evalf(gamma^exp(1)), confrac);

A328339 Simple continued fraction expansion of Gamma(exp(gamma)+1).

Original entry on oeis.org

1, 1, 1, 1, 6, 15, 1, 4, 2, 1, 11, 2, 3, 1, 1, 13, 1, 1, 1, 1, 5, 1, 27, 1, 37, 1, 1, 2, 2, 2, 40, 1, 3, 1, 5, 1, 1, 3, 3942, 3, 2, 1, 13, 3, 11, 1, 2, 1, 15, 1, 1, 2, 1, 51, 37, 1, 1, 13, 4, 1, 1, 2, 5, 1, 1, 2, 1, 1, 5, 1, 75, 1, 16, 6, 2, 2, 1, 1, 7, 2, 4
Offset: 0

Views

Author

Daniel Hoyt, Oct 12 2019

Keywords

Comments

'Gamma' is the gamma function, and 'gamma' is the Euler-Mascheroni constant.
Approximation of Gamma(exp(gamma)+1) in decimal: 1.6501566139104548059...

Crossrefs

Programs

  • Mathematica
    ContinuedFraction[Gamma[1 + Exp[EulerGamma]], 81] (* Amiram Eldar, Oct 13 2019 *)
  • PARI
    contfrac(gamma(exp(Euler)+1)) \\ Michel Marcus, Nov 04 2019

Formula

Gamma(exp(gamma)+1) = Gamma(exp(gamma)) * exp(gamma).
Showing 1-4 of 4 results.