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.

User: Jan Mangaldan

Jan Mangaldan's wiki page.

Jan Mangaldan has authored 2 sequences.

A336061 Numerators of coefficients associated with the second virial coefficient for rigid spheres with imbedded point dipoles.

Original entry on oeis.org

1, 1, 29, 11, 13, 17, 523, 31, 66197, 83651, 21253, 3660541, 520783, 668861, 3322147, 30013913, 12938197, 4073039057, 310878307, 6867070733, 668207557, 104732138813, 56875471, 253267848881, 6285904022089, 913083596083, 2612577367192619, 3420422655984353
Offset: 1

Author

Jan Mangaldan, Jul 07 2020

Keywords

Examples

			1/3, 1/75, 29/55125, 11/694575, 13/36018675, 17/2678348673, 523/5934977173125, ...
		

References

  • J. O. Hirschfelder, C. F. Curtiss, and R. B. Bird, Molecular Theory of Gases and Liquids, John Wiley & Sons, Inc., 1964, pages 210-211.

Crossrefs

Cf. A006134, A336062 (denominators).

Programs

  • Mathematica
    Table[Numerator[4^k Sum[Binomial[2 j, j]/Binomial[2 k, k], {j, 0, k}]/((2 k)! (2 k - 1) (2 k + 1)^2)], {k, 20}]
    Table[Numerator[4^k Hypergeometric2F1[1, -k, 1/2 - k, 1/4]/((2 k)! (2 k - 1) (2 k + 1)^2)], {k, 20}]
  • PARI
    a(n)={numerator(4^n*sum(j=0, n, binomial(2*j,j))/(binomial(2*n,n)*(2*n)!*(2*n-1)*(2*n+1)^2))} \\ Andrew Howroyd, Jul 07 2020

Formula

a(n) = numerator(1/(8 * Pi * (2*n)! * (2*n - 1)) * Integral_{w=0..2*Pi} Integral_{v=0..Pi} Integral_{u=0..Pi} (2 * cos(u) * cos(v) - sin(u) * sin(v) * cos(w))^(2 * n) * sin(u) * sin(v)).
a(n) = numerator(4^n * hypergeom([1, -n], [1/2 - n], 1/4)/((2 * n)! (2 * n - 1) (2 * n + 1)^2)).
a(n) = numerator(4^n*(Sum_{j=0..n} binomial(2*j,j))/(binomial(2*n,n)*(2*n)!*(2*n-1)*(2*n+1)^2)).
A336061(n)/A336062(n) ~ exp(2*n) / (12*sqrt(Pi) * n^(2*n + 7/2)). - Vaclav Kotesovec, Jul 14 2020

A336062 Denominators of coefficients associated with the second virial coefficient for rigid spheres with imbedded point dipoles.

Original entry on oeis.org

3, 75, 55125, 694575, 36018675, 2678348673, 5934977173125, 31414073315625, 7287392748056045625, 1197275761489443260625, 46668548892583246253625, 1437557979280466067633984375, 42189201565839765028388671875, 12773202666073647259994954296875, 16951256433371736928038065776171875
Offset: 1

Author

Jan Mangaldan, Jul 07 2020

Keywords

Examples

			1/3, 1/75, 29/55125, 11/694575, 13/36018675, 17/2678348673, 523/5934977173125, ...
		

References

  • J. O. Hirschfelder, C. F. Curtiss, and R. B. Bird, Molecular Theory of Gases and Liquids, John Wiley & Sons, Inc., 1964, pages 210-211.

Crossrefs

Cf. A006134, A336061 (numerators).

Programs

  • Mathematica
    Table[Denominator[4^k Sum[Binomial[2 j, j]/Binomial[2 k, k], {j, 0, k}]/((2 k)! (2 k - 1) (2 k + 1)^2)], {k, 20}]
    Table[Denominator[4^k Hypergeometric2F1[1, -k, 1/2 - k, 1/4]/((2 k)! (2 k - 1) (2 k + 1)^2)], {k, 20}]
  • PARI
    a(n)={denominator(4^n*sum(j=0, n, binomial(2*j,j))/(binomial(2*n,n)*(2*n)!*(2*n-1)*(2*n+1)^2))} \\ Andrew Howroyd, Jul 07 2020

Formula

a(n) = denominator(1/(8 * Pi * (2*n)! * (2*n - 1)) * Integral_{w=0..2*Pi} Integral_{v=0..Pi} Integral_{u=0..Pi} (2 * cos(u) * cos(v) - sin(u) * sin(v) * cos(w))^(2 * n) * sin(u) * sin(v)).
a(n) = denominator(4^n * hypergeom([1, -n], [1/2 - n], 1/4)/((2 * n)! (2 * n - 1) (2 * n + 1)^2)).
a(n) = denominator(4^n*(Sum_{j=0..n} binomial(2*j,j))/(binomial(2*n,n)*(2*n)!*(2*n-1)*(2*n+1)^2)).
A336061(n)/A336062(n) ~ exp(2*n) / (12*sqrt(Pi) * n^(2*n + 7/2)). - Vaclav Kotesovec, Jul 14 2020