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.

A371930 Decimal expansion of Pi^(1/2)*Gamma(1/14)/(7*Gamma(4/7)).

Original entry on oeis.org

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

Views

Author

Takayuki Tatekawa, Apr 12 2024

Keywords

Comments

Constants from generalized Pi integrals: the case of n=14.
In general, for k > 0, Integral_{x=0..1} 1/sqrt(1 - x^k) dx = 2^(2/k) * Gamma(1 + 1/k)^2 / Gamma(1 + 2/k) = 2^(2/k - 1) * Gamma(1/k)^2 / (k*Gamma(2/k)). - Vaclav Kotesovec, Apr 15 2024

Examples

			2.191450245201078533946264870311...
		

Crossrefs

Programs

  • Maple
    Beta(1/14, 1/2) / 7: evalf(%, 90); # Peter Luschny, Apr 14 2024
  • Mathematica
    RealDigits[Sqrt[Pi]/7*Gamma[1/14]/Gamma[4/7], 10, 5001][[1]]

Formula

Equals 2*Integral_{x=0..1} dx/sqrt(1-x^14).
Equals Beta(1/14, 1/2) / 7. - Peter Luschny, Apr 14 2024
Equals Gamma(1/14)^2 / (7 * 2^(6/7) * Gamma(1/7)). - Vaclav Kotesovec, Apr 15 2024