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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.

A244659 Decimal expansion of 4*K/Pi, a constant appearing in the asymptotic evaluation of the number of non-hypotenuse numbers not exceeding a given bound, where K is the Landau-Ramanujan constant.

Original entry on oeis.org

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

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Author

Jean-François Alcover, Jul 04 2014

Keywords

Examples

			0.973039776771781994254491281173646811...
		

References

  • Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, 2.3 Landau-Ramanujan Constant, p. 101.

Crossrefs

Programs

  • Mathematica
    digits = 100; LandauRamanujan[n_] := With[{K = Ceiling[Log[2, n*Log[3, 10]]]}, N[Product[(((1-2^(-2^k))*4^2^k*Zeta[2^k])/(Zeta[2^k, 1/4] - Zeta[2^k, 3/4]))^2^(-k-1), {k, 1, K}]/Sqrt[2], n]]; K = LandauRamanujan[digits+5]; RealDigits[4*K/Pi, 10, digits] // First (* after Victor Adamchik *)