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.

A254345 Decimal expansion of gamma_1(2/3), the first generalized Stieltjes constant at 2/3 (negated).

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Jan 29 2015

Keywords

Examples

			-0.5989062842859892925678760212692502566639134078175714915865...
		

Crossrefs

Cf. A001620 (gamma), A082633 (gamma_1), A254327 (gamma_1(1/2)), A254331 (gamma_1(1/3)), A254347 (gamma_1(1/4)), A254348 (gamma_1(3/4)), A254349 (gamma_1(1/6)), A254350 (gamma_1(5/6)), A251866 (gamma_1(1/5)), A255188 (gamma_1(1/8)), A255189 (gamma_1(1/12)).

Programs

  • Maple
    evalf(int((-12*arctan(3*x*(1/2))+9*x*log(4/9+x^2))/((-1+exp(2*Pi*x))*(9*x^2+4)), x = 0..infinity) - (3/4+(1/2)*log(3/2))*log(3/2), 120); # Vaclav Kotesovec, Jan 29 2015
  • Mathematica
    gamma1[2/3] = (1/12)*(Sqrt[3]*Pi*(2*EulerGamma + Log[(576*Pi^5)/Gamma[1/6]^6]) - 6*(EulerGamma*Log[27] + Log[3]*Log[18*Pi] - 2*StieltjesGamma[1] + Derivative[2, 0][Zeta][0, 1/3] + Derivative[2, 0][Zeta][0, 2/3])) // Re; RealDigits[gamma1[2/3], 10, 105] // First
    (* Or, from Mma version 7 up: *) RealDigits[StieltjesGamma[1, 2/3], 10, 105] // First

Formula

Equals integral_[0..infinity] (-12*arctan(3*x/2) + 9*x*log(4/9 + x^2))/((-1 + exp(2*Pi*x))*(4 + 9*x^2)) dx - (3/4 + (1/2)*log(3/2))*log(3/2).