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 19 results. Next

A097663 Decimal expansion of the constant 3*exp(psi(1/3) + EulerGamma), where EulerGamma is the Euler-Mascheroni constant (A001620) and psi(x) is the digamma function.

Original entry on oeis.org

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

Views

Author

Paul D. Hanna, Aug 25 2004

Keywords

Comments

This constant appears in Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link) and is involved in the exact determination of asymptotic limits of certain order-3 linear recursions with varying coefficients (see A097677 for example).

Examples

			0.23311909318456411730537562326544289574460858702592456414096...
		

References

  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); Exp(-Pi(R)/Sqrt(12))/Sqrt(3); // G. C. Greubel, Sep 07 2018
  • Mathematica
    RealDigits[1/Sqrt[3]*E^(-Pi/Sqrt[12]), 10, 105][[1]] (* Robert G. Wilson v, Aug 28 2004 *)
  • PARI
    3*exp(psi(1/3)+Euler)
    

Formula

Equals exp(-Pi/sqrt(12))/sqrt(3).

Extensions

More terms from Robert G. Wilson v, Aug 28 2004
Offset corrected by R. J. Mathar, Feb 05 2009

A097676 Decimal expansion of the constant 8*exp(psi(7/8) + EulerGamma), where EulerGamma is the Euler-Mascheroni constant (A001620) and psi(x) is the digamma function.

Original entry on oeis.org

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

Views

Author

Paul D. Hanna, Aug 25 2004

Keywords

Comments

This constant appears in Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link) and is involved in the exact determination of asymptotic limits of certain order-8 linear recursions with varying coefficients (see A097682 for example).

Examples

			c = 6.37663248941667785500176259382510790626743532678646216767306...
		

References

  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField();
    (1+Sqrt(2))^(-Sqrt(2))/2*Exp(Pi(R)/2*(1+Sqrt(2))); // G. C. Greubel, Sep 07 2018
  • Mathematica
    RealDigits[(1 + Sqrt[2])^(-Sqrt[2])/2E^(Pi/2*(1 + Sqrt[2])), 10, 105][[1]] (* Robert G. Wilson v, Aug 27 2004 *)
  • PARI
    8*exp(psi(7/8)+Euler)
    

Formula

c = (1+sqrt(2))^(-sqrt(2))/2*exp(Pi/2*(1+sqrt(2))).

Extensions

More terms from Robert G. Wilson v, Aug 27 2004

A097682 E.g.f.: (1/(1-x^8))*exp( 8*sum_{i>=0} x^(8*i+1)/(8*i+1) ) for an order-8 linear recurrence with varying coefficients.

Original entry on oeis.org

1, 8, 64, 512, 4096, 32768, 262144, 2097152, 16817536, 137443328, 1215668224, 13131579392, 186802241536, 3194809745408, 57299125141504, 1002518381330432, 16747075923705856, 268695698674024448, 4294396462470529024
Offset: 0

Views

Author

Paul D. Hanna, Sep 01 2004

Keywords

Comments

Limit_{n->inf} n*n!/a(n) = 8*c = 0.0259289826... where c = 8*exp(psi(1/8)+EulerGamma) = 0.0032411228...(A097673) and EulerGamma is the Euler-Mascheroni constant (A001620) and psi() is the Digamma function (see Mathworld link).

Examples

			The sequence {1, 8, 64/2!, 512/3!, 4096/4!, 32768/5!, 262144/6!,...} is generated by a recursion described by Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link).
		

References

  • Mohammad K. Azarian, Problem 1218, Pi Mu Epsilon Journal, Vol. 13, No. 2, Spring 2010, p. 116. Solution published in Vol. 13, No. 3, Fall 2010, pp. 183-185.
  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • PARI
    {a(n)=n!*polcoeff(1/(1-x^8)*exp(8*sum(i=0,n,x^(8*i+1)/(8*i+1)))+x*O(x^n),n)}
    
  • PARI
    a(n)=if(n<0,0,if(n==0,1,8*a(n-1)+if(n<8,0,n!/(n-8)!*a(n-8))))

Formula

For n>=8: a(n) = 8*a(n-1) + n!/(n-8)!*a(n-8); for n<8: a(n)=8^n. E.g.f.: 1/(1-x^8)*(1+x)/(1-x)* ((1+sqrt(2)*x+x^2)/(1-sqrt(2)*x+x^2))^(1/sqrt(2))* exp(sqrt(2)*atan(sqrt(2)*x/(1-x^2))+2*atan(x)).

A097665 Decimal expansion of the constant 4*exp(psi(1/4) + EulerGamma), where EulerGamma is the Euler-Mascheroni constant (A001620) and psi(x) is the digamma function.

Original entry on oeis.org

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

Views

Author

Paul D. Hanna, Aug 25 2004

Keywords

Comments

This constant appears in Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link) and is involved in the exact determination of asymptotic limits of certain order-4 linear recursions with varying coefficients (see A097679 for example).

Examples

			c = 0.10393978817538095427347780991748938501693892081588480403756...
		

References

  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • Mathematica
    RealDigits[1/2*E^(-Pi/2), 10, 105][[1]] (* Robert G. Wilson v, Aug 28 2004 *)
  • PARI
    4*exp(psi(1/4)+Euler)

Formula

c = 1/2*exp(-Pi/2).

Extensions

More terms from Robert G. Wilson v, Aug 28 2004

A097677 E.g.f.: (1/(1-x^3))*exp( 3*sum_{i>=0} x^(3*i+1)/(3*i+1) ) for an order-3 linear recurrence with varying coefficients.

Original entry on oeis.org

1, 3, 9, 33, 171, 1053, 7119, 57267, 525609, 5164803, 56726649, 690532857, 8889138531, 124010345277, 1880154795519, 29907812576187, 506398197859281, 9190226159295363, 173999328850897641, 3466197108906552657
Offset: 0

Views

Author

Paul D. Hanna, Sep 01 2004

Keywords

Comments

Limit_{n->inf} n*n!/a(n) = 3*c = 0.6993572795... where c = 3*exp(psi(1/3)+EulerGamma) = 0.2331190931...(A097663) and EulerGamma is the Euler-Mascheroni constant (A001620) and psi() is the Digamma function.

Examples

			The sequence {1, 3, 9/2!, 33/3!, 171/4!, 1053/5!, 7119/6!, 57267/7!,...} is generated by a recursion described by Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link).
		

References

  • Mohammad K. Azarian, Problem 1218, Pi Mu Epsilon Journal, Vol. 13, No. 2, Spring 2010, p. 116. Solution published in Vol. 13, No. 3, Fall 2010, pp. 183-185.
  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • PARI
    {a(n)=n!*polcoeff(1/(1-x^3)*exp(3*sum(i=0,n,x^(3*i+1)/(3*i+1)))+x*O(x^n),n)}
    
  • PARI
    a(n)=if(n<0,0,if(n==0,1,3*a(n-1)+if(n<3,0,n!/(n-3)!*a(n-3))))

Formula

For n>=3: a(n) = 3*a(n-1) + n!/(n-3)!*a(n-3); for n<3: a(n)=3^n. E.g.f.: 1/sqrt((1-x^3)*(1-x)^3)*exp(sqrt(3)*atan(sqrt(3)*x/(2+x))).

A097680 E.g.f.: (1/(1-x^5))*exp( 5*sum_{i>=0} x^(5*i+1)/(5*i+1) ) for an order-5 linear recurrence with varying coefficients.

Original entry on oeis.org

1, 5, 25, 125, 625, 3245, 19825, 162125, 1650625, 17703125, 186644425, 2032320125, 25569960625, 382772328125, 6166860390625, 98093486946125, 1555728351450625, 26765871718953125, 527380555479765625, 11241893092061328125
Offset: 0

Views

Author

Paul D. Hanna, Sep 01 2004

Keywords

Comments

Limit_{n->inf} n*n!/a(n) = 5*c = 0.2247091438... where c = 5*exp(psi(1/5)+EulerGamma) = 0.0449418287...(A097667) and EulerGamma is the Euler-Mascheroni constant (A001620) and psi() is the Digamma function (see Mathworld link).

Examples

			The sequence {1, 5, 25/2!, 125/3!, 625/4!, 3245/5!, 19825/6!, 162125/7!,...} is generated by a recursion described by Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link).
		

References

  • Mohammad K. Azarian, Problem 1218, Pi Mu Epsilon Journal, Vol. 13, No. 2, Spring 2010, p. 116. Solution published in Vol. 13, No. 3, Fall 2010, pp. 183-185.
  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • PARI
    {a(n)=n!*polcoeff(1/(1-x^5)*exp(5*sum(i=0,n,x^(5*i+1)/(5*i+1)))+x*O(x^n),n)}
    
  • PARI
    a(n)=if(n<0,0,if(n==0,1,5*a(n-1)+if(n<5,0,n!/(n-5)!*a(n-5))))

Formula

For n>=5: a(n) = 5*a(n-1) + n!/(n-5)!*a(n-5); for n<5: a(n)=5^n. E.g.f.: B(x)*exp(C(x)) where B(x) = 1/(1-x^5)/(1-x)*(1+phi*x+x^2)^(phi/2)/(1-x/phi+x^2)^(1/phi/2) and C(x) = 5^(1/4)*sqrt(phi)*atan(5^(1/4)*sqrt(phi)*x/(2-x/phi)) + 5^(1/4)/sqrt(phi)*atan(5^(1/4)/sqrt(phi)*x/(2+phi*x)) and where phi=(sqrt(5)+1)/2.

A097681 E.g.f.: (1/(1-x^6))*exp( 6*sum_{i>=0} x^(6*i+1)/(6*i+1) ) for an order-6 linear recurrence with varying coefficients.

Original entry on oeis.org

1, 6, 36, 216, 1296, 7776, 47376, 314496, 2612736, 28740096, 368395776, 4796983296, 60300205056, 750367328256, 10151357239296, 164475953381376, 3110937349718016, 61410199093641216, 1174438559356747776
Offset: 0

Views

Author

Paul D. Hanna, Sep 01 2004

Keywords

Comments

Limit_{n->inf} n*n!/a(n) = 6*c = 0.1140186893... where c = 6*exp(psi(1/6)+EulerGamma) = 0.0190031148...(A097671) and EulerGamma is the Euler-Mascheroni constant (A001620) and psi() is the Digamma function (see Mathworld link).

Examples

			The sequence {1, 6, 36/2!, 216/3!, 1296/4!, 7776/5!, 47376/6!,...} is generated by a recursion described by Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link).
		

References

  • Mohammad K. Azarian, Problem 1218, Pi Mu Epsilon Journal, Vol. 13, No. 2, Spring 2010, p. 116. Solution published in Vol. 13, No. 3, Fall 2010, pp. 183-185.
  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • PARI
    {a(n)=n!*polcoeff(1/(1-x^6)*exp(6*sum(i=0,n,x^(6*i+1)/(6*i+1)))+x*O(x^n),n)}
    
  • PARI
    a(n)=if(n<0,0,if(n==0,1,6*a(n-1)+if(n<6,0,n!/(n-6)!*a(n-6))))

Formula

For n>=6: a(n) = 6*a(n-1) + n!/(n-6)!*a(n-6); for n<6: a(n)=6^n. E.g.f.: 1/(1-x^6)*(1+x)/(1-x)*sqrt((1+x+x^2)/(1-x+x^2))* exp(sqrt(3)*atan(sqrt(3)*x/(1-x^2))).

A097664 Decimal expansion of the constant 3*exp(psi(2/3) + EulerGamma), where EulerGamma is the Euler-Mascheroni constant (A001620) and psi(x) is the digamma function.

Original entry on oeis.org

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

Views

Author

Paul D. Hanna, Aug 25 2004

Keywords

Comments

This constant appears in Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link) and is involved in the exact determination of asymptotic limits of certain order-3 linear recursions with varying coefficients (see A097678 for example).

Examples

			c = 1.42988430840123420566179042477513809656498236767564464887634...
		

References

  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); (1/Sqrt(3))*Exp(Pi(R)/Sqrt(12)); // G. C. Greubel, Aug 27 2018
  • Mathematica
    RealDigits[1/Sqrt[3]*E^(Pi/Sqrt[12]), 10, 105][[1]] (* Robert G. Wilson v, Aug 28 2004 *)
  • PARI
    3*exp(psi(2/3)+Euler)
    

Formula

c = 1/sqrt(3)*exp(Pi/sqrt(12)).

Extensions

More terms from Robert G. Wilson v, Aug 28 2004

A097666 Decimal expansion of the constant 4*exp(psi(3/4) + EulerGamma), where EulerGamma is the Euler-Mascheroni constant (A001620) and psi(x) is the digamma function.

Original entry on oeis.org

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

Views

Author

Paul D. Hanna, Aug 25 2004

Keywords

Comments

This constant appears in Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link) and is involved in the exact determination of asymptotic limits of certain order-4 linear recursions with varying coefficients (see A097679 for example).

Examples

			c = 2.40523869048267582773651783335191656319508543733226747001040...
		

References

  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); Exp(Pi(R)/2)/2; // G. C. Greubel, Sep 07 2018
  • Mathematica
    RealDigits[1/2*E^(Pi/2), 10, 105][[1]] (* Robert G. Wilson v, Aug 27 2004 *)
  • PARI
    4*exp(psi(3/4)+Euler)
    

Formula

c = 1/2*exp(Pi/2).

Extensions

More terms from Robert G. Wilson v, Aug 27 2004

A097667 Decimal expansion of the constant 5*exp(psi(1/5) + EulerGamma), where EulerGamma is the Euler-Mascheroni constant (A001620) and psi(x) is the digamma function.

Original entry on oeis.org

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

Views

Author

Paul D. Hanna, Aug 25 2004

Keywords

Comments

This constant appears in Benoit Cloitre's generalized Euler-Gauss formula for the Gamma function (see Cloitre link) and is involved in the exact determination of asymptotic limits of certain order-5 linear recursions with varying coefficients (see A097680 for example).

Examples

			c = 0.04494182877920882060846739642766520340238594371059869805861...
		

References

  • A. M. Odlyzko, Linear recurrences with varying coefficients, in Handbook of Combinatorics, Vol. 2, R. L. Graham, M. Grotschel and L. Lovasz, eds., Elsevier, Amsterdam, 1995, pp. 1135-1138.

Crossrefs

Programs

  • Mathematica
    RealDigits[ GoldenRatio^(-Sqrt[5]/2)/5^(1/4)*E^(-Pi/2*Sqrt[1 + 2/Sqrt[5]]), 10, 104][[1]] (* Robert G. Wilson v, Aug 27 2004 *)
    Join[{0}, RealDigits[N[5*Exp[PolyGamma[1/5] + EulerGamma], 120], 10, 100][[1]]] (* G. C. Greubel, Dec 31 2016 *)
  • PARI
    5*exp(psi(1/5)+Euler)

Formula

c = ((sqrt(5)+1)/2)^(-sqrt(5)/2)/5^(1/4)*exp(-Pi/2*sqrt(1+2/sqrt(5))).

Extensions

More terms from Robert G. Wilson v, Aug 27 2004
Showing 1-10 of 19 results. Next