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 1-10 of 11 results. Next

A257955 Decimal expansion of Gamma(1/Pi).

Original entry on oeis.org

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

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Comments

The reference gives an interesting product representation in terms of rational multiple of 1/Pi for Gamma(1/Pi).

Examples

			2.8112975146708616421227908037104816935281655223291765...
		

Crossrefs

Programs

  • Maple
    evalf(GAMMA(1/Pi), 117);
  • Mathematica
    RealDigits[Gamma[1/Pi], 10, 117][[1]]
  • PARI
    default(realprecision, 117); gamma(1/Pi)

A257959 Decimal expansion of the Digamma function at 1/2 + 1/Pi, negated.

Original entry on oeis.org

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

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Author

Keywords

Comments

The reference gives an interesting series representation with rational coefficients for Psi(1/2 + 1/Pi) = -log(Pi) + 1/4 + 1/16 - 5/576 - 13/512 - 569/25600 -539/36864 - 98671/12042240 - 16231/3932160 - ...

Examples

			-0.9236326759613377346000263347486747139894893215261027...
		

Crossrefs

Programs

  • Maple
    evalf(Psi(1/2+1/Pi), 120);
  • Mathematica
    RealDigits[PolyGamma[1/2+1/Pi], 10, 120][[1]]
  • PARI
    default(realprecision, 120); psi(1/2+1/Pi)

A257957 Decimal expansion of log(Gamma(1/Pi)).

Original entry on oeis.org

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

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Author

Keywords

Comments

The reference gives an interesting series representation with rational coefficients for log(Gamma(1/Pi)) = (1-1/Pi)*log(Pi) - 1/Pi + log(2)/2 + (1 + 1/4 + 1/12 + 1/32 + 1/75 + 1/144 + 13/2880 + 157/46080 + ...)/(2*Pi).
The value log(Gamma(1/Pi)) is also intimately related to integral_{x=0..1} arctan(arctanh(x))/x (A257963).

Examples

			1.0336461257655827064855374553316178667100308701595988...
		

Crossrefs

Programs

  • Maple
    evalf(log(GAMMA(1/Pi)), 120);
  • Mathematica
    RealDigits[Log[Gamma[1/Pi]], 10, 120][[1]]
  • PARI
    default(realprecision, 120); log(gamma(1/Pi))

A339135 Decimal expansion of J = 2*log(2)/3 - Re(Psi(1/2 + i*sqrt(3)/2)), where Psi is the digamma function and i=sqrt(-1).

Original entry on oeis.org

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

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Author

Artur Jasinski, Nov 25 2020

Keywords

Comments

Generally in the literature there is no explicit formula for the real part of the function Psi(x + i*y) when y != 0.
Up to now there is no explicit formula expressing the constant J in terms of other mathematical constants.

Examples

			J = 0.677024679102993347...
		

Crossrefs

Programs

  • Maple
    evalf(1 + 2*log(2)/3 - Psi(0, 5/2 - sqrt(3)*I/2)/2 - Psi(0, 5/2 + sqrt(3)*I/2)/2, 100); # Vaclav Kotesovec, Nov 26 2020
  • Mathematica
    RealDigits[N[Re[2 Log[2]/3 - PolyGamma[0, 1/2 + I Sqrt[3]/2]], 110]][[1]]
    Chop[N[1 + 2*Log[2]/3 - PolyGamma[0, 5/2 - I*Sqrt[3]/2]/2 - PolyGamma[0, 5/2 + I*Sqrt[3]/2]/2, 120]] (* Vaclav Kotesovec, Nov 26 2020 *)
  • PARI
    2*log(2)/3 - real(psi(1/2 + I*sqrt(3)/2)) \\ Michel Marcus, Nov 25 2020

Formula

J = -log(2)/3 - (1/2)*Pi/cosh(Pi*sqrt(3)/2) - Re(Psi(1/4 + i*sqrt(3)/4)).
J = -log(2)/3 + (1/2)*Pi/cosh(Pi*sqrt(3)/2) - Re(Psi(3/4 + i*sqrt(3)/4)).
J = 3 + gamma + (2/3)*log(2) - (1/2)* sqrt(3)*Pi*tanh(Pi*sqrt(3)/2) - 3*(Sum_{n>=1} zeta(3*n)-1), where zeta is Riemann zeta function and gamma is Euler gamma constant see A001620.
J = -(1/2) + gamma + (2/3)*log(2) + (3/2)*(Sum_{n>=1} zeta(3*n+1)-1).
J = -1 + gamma + (2/3)*log(2) + (1/2)*sqrt(3)*Pi*tanh(Pi*sqrt(3)/2) - 3*(Sum_{n>=0} zeta(3*n+2)-1).
J = -(3/8) + gamma + (2/3)*log(2) + (3/2)*(Sum_{n>=1} zeta(6*n+1)-1).
J = 1/4 + gamma + (2/3)*log(2) - 3*(Sum_{n>=0} zeta(6*n+3)-1).
J = -(1/4) + gamma + (2/3)*log(2) - 3 (Sum_{n>=0} zeta(6*n+5)-1).
J = (11/12 - (1/4)*i*sqrt(3))*Psi(1/2 + i*sqrt(3)/2) + (-(5/4) + (1/4)*i*sqrt(3))*Psi(-(1/2) - i*sqrt(3)/2) + (-(17/24) + (1/8)*i*sqrt(3))* Psi(1/4 + i*sqrt(3)/4) + (3/8 - (1/8)*i*sqrt(3))*Psi(-(1/4) - i*sqrt(3)/4) + (-(17/24) + (1/8)*i*sqrt(3))*Psi(3/4 + i*sqrt(3)/4) + (3/8 - (1/8)*i*sqrt(3))*Psi(-(3/4) - i*sqrt(3)/4).
J = 2*log(2)/3 - Integral_{t=0..infinity} cosh(t)/t - sinh(t)/t - (cos(sqrt(3)*t)*cosh(t/2))/(1 - cosh(t) + sinh(t)) + (cos(sqrt(3)*t)*sinh(t/2))/(1 - cosh(t) + sinh(t)).
J = gamma + (1/6)*Sum_{t>=1} (6*t^3-4*t^2-4*t-1)/(t*(t+1)*(2t+1)*(t^2+t+1)).
Equals 1 + 2*log(2)/3 - Psi(0, 5/2 - i*sqrt(3)/2)/2 - Psi(0, 5/2 + i*sqrt(3)/2)/2. - Vaclav Kotesovec, Nov 26 2020

A269545 Decimal expansion of Gamma(Pi).

Original entry on oeis.org

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

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Keywords

Examples

			2.2880377953400324179595889090602339228896881533562224...
		

Crossrefs

Programs

  • MATLAB
    format long; gamma(pi)
  • Maple
    evalf(GAMMA(Pi), 120);
  • Mathematica
    RealDigits[Gamma[Pi], 10, 120][[1]]
  • PARI
    default(realprecision, 120); gamma(Pi)
    

Formula

Equals Integral_{x >= 0} x^(Pi-1)/e^x dx (Euler integral of the second kind).

A269546 Decimal expansion of log(Gamma(Pi)).

Original entry on oeis.org

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

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Author

Keywords

Comments

Gamma(x) is the Gamma function (Euler's integral of the second kind).

Examples

			0.8276945923234371015295785584523599511535017341207373...
		

Crossrefs

Programs

  • MATLAB
    format long; log(gamma(pi))
  • Maple
    evalf(lnGAMMA(Pi), 120);
  • Mathematica
    RealDigits[LogGamma[Pi], 10, 120][[1]]
  • PARI
    default(realprecision, 120); lngamma(Pi)
    

A269547 Decimal expansion of Psi(Pi).

Original entry on oeis.org

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

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Author

Keywords

Comments

Psi(x) is the digamma function (logarithmic derivative of the Gamma function).

Examples

			0.9772133079420067332920694864061823436408346099943256...
		

Crossrefs

Programs

  • MATLAB
    format long; psi(pi)
  • Maple
    evalf(Psi(Pi), 120)
  • Mathematica
    RealDigits[PolyGamma[Pi], 10, 120][[1]]
  • PARI
    default(realprecision, 120); psi(Pi)
    

A269557 Decimal expansion of Gamma(log(2)).

Original entry on oeis.org

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

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Author

Keywords

Comments

Gamma(x) is the Gamma function (Euler's integral of the second kind).

Examples

			1.3090409112814812698245325213959295756125890319181890...
		

Crossrefs

Programs

  • MATLAB
    format long; gamma(log(2))
  • Maple
    evalf(GAMMA(ln(2)), 120);
  • Mathematica
    RealDigits[Gamma[Log[2]], 10, 120][[1]]
  • PARI
    default(realprecision, 120); gamma(log(2))
    

A269558 Decimal expansion of log(Gamma(log(2))).

Original entry on oeis.org

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

Views

Author

Keywords

Comments

Gamma(x) is the Gamma function (Euler's integral of the second kind).

Examples

			0.2692947402831312429499165832117128248889035102111661...
		

Crossrefs

Programs

  • MATLAB
    format long; log(gamma(log(2)))
  • Maple
    evalf(lnGAMMA(ln(2)), 120);
  • Mathematica
    RealDigits[LogGamma[Log[2]], 10, 120][[1]]
  • PARI
    default(realprecision, 120); lngamma(log(2))
    

A269559 Decimal expansion of Psi(log(2)), negated.

Original entry on oeis.org

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

Views

Author

Keywords

Comments

Psi(x) is the digamma function (logarithmic derivative of the Gamma function).

Examples

			-1.2395972796176185082441275516860842454332895226874208...
		

Crossrefs

Programs

  • MATLAB
    format long; psi(log(2))
  • Maple
    evalf(Psi(ln(2)), 120);
  • Mathematica
    RealDigits[PolyGamma[Log[2]], 10, 120][[1]]
  • PARI
    default(realprecision, 120); psi(log(2))
    
Showing 1-10 of 11 results. Next