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.

A039661 Decimal expansion of exp(Pi).

Original entry on oeis.org

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

Views

Author

Keywords

Comments

e^Pi and Pi^e (A059850) differ by hardly 3% in magnitude. The determination of the inequality sign between them does not require their actual evaluation, the result being immediate from the basic facts Pi>e and log(x+1)0) yields log(Pi)
The formulas give e^Pi, not a(n). Note that e^Pi - Pi = 19.999099979...; that's why e^Pi and 20 + Pi have many common decimal digits. - M. F. Hasler, Oct 24 2009
e^Pi is transcendental, as proved by Gelfond. - Charles R Greathouse IV, May 07 2013
Nesterenko proves that this constant is algebraically independent of Pi and Gamma(1/4) over Q. - Charles R Greathouse IV, Nov 11 2013
Sum of the volumes of all even-dimensional unit spheres. - Paolo Xausa, Nov 14 2021

Examples

			23.1406926327792690...
		

References

  • L. Berggren, J. Borwein, and P. Borwein, "Pi: a source Book", second edition, Springer, p. 422.
  • David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, Revised edition 1987. See p. 101.

Crossrefs

Cf. A059850 (Pi^e).
Cf. A058287 = contfrac(e^Pi), A058288 = contfrac(Pi^e).

Programs

  • Mathematica
    RealDigits[N[E^Pi,200]] (* Vladimir Joseph Stephan Orlovsky, May 27 2010 *)
  • PARI
    default(realprecision, 20080); x=exp(1)^Pi/10; for (n=2, 20000, d=floor(x); x=(x-d)*10; write("b039661.txt", n, " ", d)); \\ Harry J. Smith, Apr 18 2009
    
  • PARI
    A039661(n)=default(realprecision,n);exp(Pi)\10^(3-n)%10 \\ M. F. Hasler, Oct 24 2009

Formula

e^Pi = 32*Product_{j>=0} (u(j+1)/u(j))^(2^(-j+1)) where u(0)=1 and v(0)=1/sqrt(2); u(n+1) = u(n)/2 + v(n)/2, v(n+1) = sqrt(u(n)*v(n)) (deduced from Salamin algorithm for Pi). - Benoit Cloitre, Aug 14 2003
e^Pi = Sum_{k>=0} a(k)/k!/2^k where a(0)=1, a(1)=6 and a(n) = (40 - 4*n + n^2)*a(n-2) for n>=2 (from expansion of exp(6*asin(x)) at x=1/2). - Jaume Oliver Lafont, Oct 21 2009
exp(Pi) ~= log(Pi) + 7*Pi. - Alexander R. Povolotsky, Oct 24 2009
Equals Sum_{k>=0} Pi^k/k!. - Paolo Xausa, Nov 14 2021

A059850 Decimal expansion of Pi^e.

Original entry on oeis.org

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

Author

Hsu, Po-Wei (Benny) (arsene_lupin(AT)intekom.co.za), Jan 13 2000

Keywords

Comments

Pi^e is conjectured to be transcendental.

Examples

			22.459157718361045473427152204543735027589315133996692...
		

References

  • C. Pickover, Wonders of Numbers, Chap. 44, "The 15 Most Famous Transcendental Numbers", Oxford University Press, NY, 2001, p. 103.
  • David Wells, The Penguin Dictionary of Curious and Interesting Numbers. Penguin Books, NY, 1986, Revised edition 1987. See p. 100.

Crossrefs

Cf. A058288.

Programs

  • Mathematica
    RealDigits[N[Pi^E,200]] (* Vladimir Joseph Stephan Orlovsky, May 27 2010 *)
  • PARI
    { default(realprecision, 20080); x=Pi^exp(1)/10; for (n=2, 20000, d=floor(x); x=(x-d)*10; write("b059850.txt", n, " ", d)); } \\ Harry J. Smith, Apr 18 2009

Extensions

More terms from James Sellers, Jan 19 2000

A064107 Continued fraction quotients for e^e = 15.15426224... (A073226).

Original entry on oeis.org

15, 6, 2, 13, 1, 3, 6, 2, 1, 1, 5, 1, 1, 1, 9, 4, 1, 1, 1, 6, 7, 1, 2, 4, 1, 2, 2, 24, 1, 2, 4, 56, 1, 1, 2, 4, 1, 75, 1, 5, 1, 2, 2, 1, 137, 2, 2, 97, 3, 16, 1, 1, 1, 1, 3, 5, 12, 1, 1, 2, 1, 53, 1, 2, 5, 3, 2, 4, 1, 2, 1, 39, 1, 2, 1, 4, 1, 11, 1, 5, 5, 1, 4, 1, 17, 12, 4, 82, 1, 4, 6, 25, 3, 2, 3
Offset: 0

Author

Labos Elemer, Sep 17 2001

Keywords

Comments

It was conjectured (but remains unproved) that this sequence is infinite and aperiodic, but it is difficult to determine who first posed this problem. - Vladimir Reshetnikov, Apr 27 2013

Examples

			15.154262241479264189760430... = 15 + 1/(6 + 1/(2 + 1/(13 + 1/(1 + ...)))). - _Harry J. Smith_, Apr 30 2009
		

Crossrefs

Cf. A058287, A058288, A073226 (decimal expansion), A159825.

Programs

  • Maple
    with(numtheory): cfrac(evalf((exp(1))^(exp(1)),2560),256,'quotients');
  • Mathematica
    ContinuedFraction[E^E,100] (* Harvey P. Dale, Sep 29 2012 *)
  • PARI
    { allocatemem(932245000); default(realprecision, 21000); x=contfrac(exp(exp(1))); for (n=1, 20000, write("b064107.txt", n-1, " ", x[n])); } \\ Harry J. Smith, Apr 30 2009

Extensions

Offset changed by Andrew Howroyd, Aug 05 2024

A116907 Continued fraction expansion for e^(-e) = 0.0659880358453125370767901875.

Original entry on oeis.org

0, 15, 6, 2, 13, 1, 3, 6, 2, 1, 1, 5, 1, 1, 1, 9, 4, 1, 1, 1, 6, 7, 1, 2, 4, 1, 2, 2, 24, 1, 2, 4, 56, 1, 1, 2, 4, 1, 75, 1, 5, 1, 2, 2, 1, 137, 2, 2, 97, 3, 16, 1, 1, 1, 1, 3, 5, 12, 1, 1, 2, 1, 53, 1, 2, 5, 3, 2, 4, 1, 2, 1, 39, 1, 2, 1, 4, 1, 11, 1, 5, 5, 1, 4, 1, 17, 12, 4, 82, 1, 4, 6, 25, 3, 2, 3, 39
Offset: 1

Author

Jonathan Vos Post, Mar 16 2006

Keywords

Comments

e^(-e) = (1/e)^e = 1/(e^e) = (reciprocal of A073226). e^(-e) = 0.0659880358453125370767901875... = 0 + 1/15+ 1/6+ 1/2+ 1/13+ 1/1+ 1/3+ 1/6+ 1/2+ ... See also: A073230 Decimal expansion of (1/e)^e. See also: A064107 Continued fraction quotients for e^e = 15.15426223. See also: A058287 Continued fraction for e^Pi. See also: A058288 Continued fraction expansion of Pi^e.

Crossrefs

Showing 1-4 of 4 results.