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.

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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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Author

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

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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

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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))
    

A034255 Related to quartic factorial numbers A007696.

Original entry on oeis.org

1, 10, 120, 1560, 21216, 297024, 4243200, 61526400, 902387200, 13355330560, 199115837440, 2986737561600, 45030812467200, 681895160217600, 10364806435307520, 158063298138439680, 2417438677411430400, 37067393053641932800, 569667303771760230400, 8772876478085107548160
Offset: 1

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Author

Keywords

Crossrefs

First column of triangle A048882.

Programs

  • Mathematica
    Rest[CoefficientList[Series[(-1+(1-16x)^(-1/4))/4,{x,0,20}],x]] (* Harvey P. Dale, May 19 2011 *)

Formula

a(n) = 4^(n-1)*A007696(n)/n!, where A007696(n) = (4*n-3)(!^4) = Product_{j=1..n} (4*j-3), n >= 1.
G.f.: (-1+(1-16*x)^(-1/4))/4.
a(n) = A048882(n, 1).
Convolution of A034385(n-1) with A025749(n), n >= 1.
D-finite with recurrence: n*a(n) + 4*(-4*n+3)*a(n-1) = 0. - R. J. Mathar, Jan 28 2020
a(n) ~ 2^(4*n-2) * n^(-3/4) / Gamma(1/4). - Amiram Eldar, Aug 18 2025

A068464 Factorial expansion of Gamma(1/4) = Sum_{n>=1} a(n)/n! with largest possible a(n), and Gamma = Euler's gamma function.

Original entry on oeis.org

3, 1, 0, 3, 0, 0, 3, 0, 5, 3, 2, 7, 0, 2, 8, 9, 16, 3, 1, 15, 18, 8, 20, 7, 23, 8, 10, 11, 28, 29, 24, 30, 3, 16, 10, 8, 31, 11, 30, 35, 5, 5, 38, 32, 31, 42, 13, 17, 43, 3, 41, 27, 1, 14, 26, 52, 38, 22, 55, 46, 6, 35, 46, 34, 24, 52, 52, 64, 62, 25, 46, 56, 3, 71, 70, 22, 53, 63, 53
Offset: 1

Views

Author

Benoit Cloitre, Mar 10 2002

Keywords

Examples

			Gamma(1/4) = A068466 = 3.6256099... = 3/1! + 1/2! + 0 + 3/4! + 0 + 0 + 3/7! + 0 + 5/9! + 3/10! + 2/11! + ... - _M. F. Hasler_, Nov 26 2018
		

Crossrefs

Cf. A007514, A068466 (decimal expansion), A068463.

Programs

  • Magma
    SetDefaultRealField(RealField(250));  [Floor(Gamma(1/4))] cat [Floor(Factorial(n)*Gamma(1/4)) - n*Floor(Factorial((n-1))*Gamma(1/4)) : n in [2..80]]; // G. C. Greubel, Nov 27 2018
    
  • Mathematica
    r:= Gamma[1/4]; Table[If[n == 1, Floor[r], Floor[n!*r]- n*Floor[(n-1)!*r] ], {n,1,100}] (* G. C. Greubel, Mar 29 2018 *)
  • PARI
    default(realprecision, 250); b = gamma(1/4); for(n=1, 80, print1(if(n==1, floor(b), floor(n!*b) - n*floor((n-1)!*b)), ", ")) \\ G. C. Greubel, Mar 29 2018
    
  • PARI
    A068464(N=90,c=gamma(precision(.25,logint(N!,10)+1)))=vector(N,n,if(n>1,c=c%1*n,c)\1) \\ - M. F. Hasler, Nov 26 2018
    
  • Sage
    def A068464(n):
        if (n==1): return floor(gamma(1/4))
        else: return expand(floor(factorial(n)*gamma(1/4)) - n*floor(factorial(n-1)*gamma(1/4)))
    [A068464(n) for n in (1..80)] # G. C. Greubel, Nov 27 2018

Formula

a(n) = floor(n!*Gamma(1/4)) - n*floor((n-1)!*Gamma(1/4)), for n > 1. - M. F. Hasler, Nov 26 2018

A225119 Decimal expansion of Integral_{x=0..Pi/2} sin(x)^(3/2) dx.

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Apr 29 2013

Keywords

Examples

			0.87401918476403993682161319663037313789425165047720772093894...
		

References

  • George Boros and Victor H. Moll, Irresistible integrals, Cambridge University Press (2006), p. 195.
  • Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 2.3 Landau-Ramanujan constant p. 102 and Section 6.1 Gauss' Lemniscate Constant p. 422.

Crossrefs

Programs

  • Maple
    evalf((1/3)*sqrt(2)*EllipticK(1/sqrt(2)), 120); # Vaclav Kotesovec, Apr 22 2015
  • Mathematica
    RealDigits[1/3*Sqrt[2]*EllipticK[1/2], 10, 100][[1]]
  • PARI
    sqrt(Pi)*gamma(1/4)/(6*gamma(3/4)) \\ G. C. Greubel, Apr 01 2017
    
  • PARI
    ellK(sqrt(1/2))*sqrt(2)/3 \\ Charles R Greathouse IV, Feb 04 2025

Formula

Equals 1/3 * sqrt(2) * ellipticK(1/2), (defined as in Mathematica).
Equals sqrt(2)/6 * Pi * hypergeom([1/2,1/2],[1],1/2).
Equals gamma(1/4)^2/(6*sqrt(2*Pi)).
Equals sqrt(Pi)*gamma(1/4)/(6*gamma(3/4)).
Equals Integral_{0..1} (1-x^2)^(1/4) dx.
Equals Integral_{0..1} sqrt(1-x^4) dx. - Charles R Greathouse IV, Aug 21 2017
Equals (2/3)*A085565. - Peter Bala, Oct 27 2019
Equals A062539/3. - Hugo Pfoertner, Dec 15 2024

A203144 Decimal expansion of Gamma(5/8).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Dec 29 2011

Keywords

Examples

			1.4345188480905567756360197394564231366322077722066673307706...
		

Programs

Formula

this * A203142 = 2^(3/4)*sqrt(Pi) * A068466. - R. J. Mathar, Jan 15 2021
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