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 12 results. Next

A256988 Decimal expansion of Sum_{k>=1} H(k)^3/k^2 where H(k) is the k-th harmonic number.

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Apr 14 2015

Keywords

Examples

			12.346581901730995381510740306055467252652960661679262328437749...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[10*Zeta[5] + (Pi^2/6)*Zeta[3], 10, 104] // First
  • PARI
    10*zeta(5) + zeta(2)*zeta(3) \\ Michel Marcus, Apr 14 2015

Formula

Equals 10*zeta(5) + zeta(2)*zeta(3) or, 10*zeta(5) + (Pi^2/6)*zeta(3).

A244675 Decimal expansion of sum_(n>=1) (H(n)^3/(n+1)^3) where H(n) is the n-th harmonic number.

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Jul 04 2014

Keywords

Examples

			0.17758688422659116882105255543380545223004150911094072394667346832845...
		

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); L:=RiemannZeta(); -11/120*Pi(R)^4*Evaluate(L,3) + 1/3*Pi(R)^2*Evaluate(L,5) + 119/16*Evaluate(L,7); // G. C. Greubel, Aug 31 2018
  • Mathematica
    RealDigits[119/16*Zeta[7] - 33/4*Zeta[3]*Zeta[4] + 2*Zeta[2]*Zeta[5], 10, 103] // First
  • PARI
    default(realprecision, 100);  -11/120*Pi^4*zeta(3) + 1/3*Pi^2*zeta(5) + 119/16*zeta(7) \\ G. C. Greubel, Aug 31 2018
    

Formula

Equals -11/120*Pi^4*zeta(3) + 1/3*Pi^2*zeta(5) + 119/16*zeta(7).

A244676 Decimal expansion of sum_(n>=1) (H(n)^3/(n+1)^6) where H(n) is the n-th harmonic number.

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Jul 04 2014

Keywords

Examples

			0.02289126788224074913774364071997743746511359015190275216397993401922...
		

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); L:=RiemannZeta(); -(37/7560)*Pi(R)^6*Evaluate(L,3) + Evaluate(L,3)^3 - (11/120)*Pi(R)^4*Evaluate(L,5) + Pi(R)^2*Evaluate(L,7)/2 + (197/24)*Evaluate(L,9); // G. C. Greubel, Aug 31 2018
  • Mathematica
    RealDigits[197/24*Zeta[9] - 33/4*Zeta[4]*Zeta[5] - 37/8*Zeta[3]*Zeta[6] + Zeta[3]^3 + 3*Zeta[2]*Zeta[7], 10, 104] // First // Prepend[#, 0]&
  • PARI
    default(realprecision, 100);  -37/7560*Pi^6*zeta(3) + zeta(3)^3 - 11/120*Pi^4*zeta(5) + 1/2*Pi^2*zeta(7) + 197/24*zeta(9) \\ G. C. Greubel, Aug 31 2018
    

Formula

Equals -37/7560*Pi^6*zeta(3) + zeta(3)^3 - 11/120*Pi^4*zeta(5) + 1/2*Pi^2*zeta(7) + 197/24*zeta(9).

A247669 Decimal expansion of A_3 = Sum_{n >= 1} H(n)^2/((2n-1)*(2n)*(2n+1))^3, where H(n) is the n-th harmonic number.

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Sep 22 2014

Keywords

Examples

			0.00464045020357812398918052923623454672526939078320273923...
		

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); L:=RiemannZeta(); 4*Log(2)^3 + ((7*Evaluate(L,3))/8 - 35/4)*Log(2)^2 - ((-(1/8))*9*Evaluate(L,2) + (7*Evaluate(L,3))/8 + (45*Evaluate(L,4))/32 - 12)*Log(2) - Evaluate(L,2)/4 - (41*Evaluate(L,3))/8 - (3/32)*Evaluate(L,2)*Evaluate(L,3) + (45*Evaluate(L,4))/64 + (17*Evaluate(L,5))/32; // G. C. Greubel, Aug 31 2018
  • Mathematica
    A3 = 4*Log[2]^3 + ((7*Zeta[3])/8 - 35/4)*Log[2]^2 - ((-(1/8))*9*Zeta[2] + (7*Zeta[3])/8 + (45*Zeta[4])/32 - 12)*Log[2] - Zeta[2]/4 - (41*Zeta[3])/8 - (3/32)*Zeta[2]*Zeta[3] + (45*Zeta[4])/64 + (17*Zeta[5])/32; Join[{0, 0}, RealDigits[A3, 10, 102] // First]
  • PARI
    4*log(2)^3 + ((7*zeta(3))/8 - 35/4)*log(2)^2 - ((-(1/8))*9*zeta(2) + (7*zeta(3))/8 + (45*zeta(4))/32 - 12)*log(2) - zeta(2)/4 - (41*zeta(3))/8 - (3/32)*zeta(2)*zeta(3) + (45*zeta(4))/64 + (17*zeta(5))/32 \\ Michel Marcus, Sep 22 2014
    

Formula

A_3 = 4*log(2)^3 + ((7*zeta(3))/8 - 35/4)*log(2)^2 - ((-(1/8))*9*zeta(2) + (7*zeta(3))/8 + (45*zeta(4))/32 - 12)*log(2) - zeta(2)/4 - (41*zeta(3))/8 - (3/32)*zeta(2)*zeta(3) + (45*zeta(4))/64 + (17*zeta(5))/32.

A247670 Decimal expansion of Sum_{n >= 0} (-1)^n*H(n)/(2n+1)^3, where H(n) is the n-th harmonic number.

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Sep 22 2014

Keywords

Examples

			-0.02857417063624359099908429512504431088603018691486...
		

Crossrefs

Programs

  • Mathematica
    s = -(Pi^3/16)*Log[2] - (7*Pi/16)*Zeta[3] + (1/512)*(PolyGamma[3, 1/4] - PolyGamma[3, 3/4]); Join[{0}, RealDigits[s, 10, 101] // First]

Formula

Equals -(Pi^3/16)*log(2) - (7*Pi/16)*zeta(3) + (1/512)*(PolyGamma(3, 1/4) - PolyGamma(3, 3/4)), where PolyGamma(n,z) gives the n-th derivative of the digamma function Psi^(n)(z).

A256987 Decimal expansion of Sum_{k>=1} H(k)*H(k,2)/k^2 where H(k) is the k-th harmonic number and H(k,2) the k-th harmonic number of order 2.

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Apr 14 2015

Keywords

Examples

			3.01423210544066604452845092794215974013923238616204702067...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[Zeta[5] + (Pi^2/6)*Zeta[3], 10, 105] // First
  • PARI
    zeta(5) + zeta(2)*zeta(3) \\ Michel Marcus, Apr 14 2015

Formula

zeta(5) + zeta(2)*zeta(3) = zeta(5) + (Pi^2/6)*zeta(3).

A384457 Decimal expansion of Sum_{k>=1} H(k)^3/2^k, where H(k) = A001008(k)/A002805(k) is the k-th harmonic number.

Original entry on oeis.org

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

Views

Author

Amiram Eldar, May 30 2025

Keywords

Examples

			3.59342794177494296025518240703339219591695480351933...
		

References

  • K. Ramachandra and R. Sitaramachandrarao, On series, integrals and continued fractions - II, Madras Univ. J., Sect. B, 51 (1988), pp. 181-198.

Crossrefs

Programs

  • Mathematica
    RealDigits[Zeta[3] + (Pi^2*Log[2] + Log[2]^3)/3, 10, 120][[1]]
  • PARI
    zeta(3) + (Pi^2*log(2) + log(2)^3)/3

Formula

Equals zeta(3) + (Pi^2*log(2) + log(2)^3)/3.

A384458 Decimal expansion of Sum_{k>=1} (-1)^(k+1)*H(k)^3/k, where H(k) = A001008(k)/A002805(k) is the k-th harmonic number.

Original entry on oeis.org

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

Views

Author

Amiram Eldar, May 30 2025

Keywords

Examples

			0.27412574654925297067883303678750470762654489295575...
		

References

  • Ali Shadhar Olaikhan, An Introduction to the Harmonic Series and Logarithmic Integrals, 2021, p. 245, eq. (4.149).
  • K. Ramachandra and R. Sitaramachandrarao, On series, integrals and continued fractions - II, Madras Univ. J., Sect. B, 51 (1988), pp. 181-198.

Crossrefs

Programs

  • Mathematica
    RealDigits[(Pi*Log[2])^2/8 + 5*Zeta[4]/8 - 9*Zeta[3]*Log[2]/8 - Log[2]^4/4, 10, 120][[1]]
  • PARI
    (Pi*log(2))^2/8 + 5*zeta(4)/8 - 9*zeta(3)*log(2)/8 - log(2)^4/4

Formula

Equals (Pi*log(2))^2/8 + 5*zeta(4)/8 - 9*zeta(3)*log(2)/8 - log(2)^4/4.

A384459 Decimal expansion of Sum_{k>=1} (-1)^k*(3*k+1)*H(k)^3/2^k, where H(k) = A001008(k)/A002805(k) is the k-th harmonic number.

Original entry on oeis.org

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

Views

Author

Amiram Eldar, May 30 2025

Keywords

Examples

			0.16440195389316542965263621650302311406441305151904...
		

References

  • K. Ramachandra and R. Sitaramachandrarao, On series, integrals and continued fractions - II, Madras Univ. J., Sect. B, 51 (1988), pp. 181-198.

Crossrefs

Programs

  • Mathematica
    RealDigits[Log[3/2]^2, 10, 120][[1]]
  • PARI
    log(3/2)^2

Formula

Equals A016578^2 = log(3/2)^2 (Ramachandra, 1981).
Equals Sum_{k>=1} (-1)^(k+1)*H(k)/((k+1)*2^k), where H(k) = A001008(k)/A002805(k) is the k-th harmonic number (Shamos, 2011).

A384460 Decimal expansion of Sum_{k>=1} (-1)^(k+1)*H(k)^2/k, where H(k) = A001008(k)/A002805(k) is the k-th harmonic number.

Original entry on oeis.org

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

Views

Author

Amiram Eldar, May 30 2025

Keywords

Examples

			0.44246018937791249521879821917465633518413362702258...
		

References

  • Ovidiu Furdui, Limits, Series, and Fractional Part Integrals, Springer, 2013, section 3.4, p. 148.

Crossrefs

Programs

  • Mathematica
    RealDigits[(9*Zeta[3] + 4*Log[2]^3 - Pi^2*Log[2])/12, 10, 120][[1]]
  • PARI
    (9*zeta(3) + 4*log(2)^3 - Pi^2*log(2))/12

Formula

Equals (9*zeta(3) + 4*log(2)^3 - Pi^2*log(2))/12.
Showing 1-10 of 12 results. Next