A340866 Decimal expansion of the Mertens constant C(5,4).

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

Offset

1,2

Comments

Data taken from Alessandro Languasco and Alessandro Zaccagnini 2007 p. 4.

References

Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 2.2 Meissel-Mertens constants (pp. 94-95).

Links

Vaclav Kotesovec, Table of n, a(n) for n = 1..497

Alessandro Languasco and Alessandro Zaccagnini, On the constant in the Mertens product for arithmetic progressions. II: Numerical values, Math. Comp. 78 (2009), 315-326.

Alessandro Languasco and Alessandro Zaccagnini, Computation of the Mertens constants - more than 100 correct digits, (2007). [in this table on page 4, the last correct digit is a(108), beyond the level there certified. - Vaclav Kotesovec, Jan 26 2021]

Alessandro Languasco and Alessandro Zaccagnini, On the constant in the Mertens product for arithmetic progressions. I. Identities, Funct. Approx. Comment. Math. Volume 42, Number 1 (2010), 17-27.

For other links see A340711.

Formula

Equals A340839*5^(1/4)*sqrt(A340004/(2*A340127)).

Equals (13*Pi^2/(24*sqrt(5)*exp(gamma)*log((1+sqrt(5))/2))*A340629/A340809)^(1/4). - Vaclav Kotesovec, Jan 25 2021

Example

1.299364547914977988160840014964265909502574970408329662016...

Mathematica

(* Using Vaclav Kotesovec's function Z from A301430. *)
$MaxExtraPrecision = 1000; digits = 121;
digitize[c_] := RealDigits[Chop[N[c, digits]], 10, digits - 1][[1]];
digitize[(13*Pi^2 / (24*Sqrt[5] * Exp[EulerGamma] * Log[(1 + Sqrt[5])/2]) * Z[5, 1, 2]^2 / (Z[5, 1, 4] * Z[5, 4, 4]))^(1/4)]

Crossrefs

Cf. A340004, A340127, A340839, A340711.

Sequence in context: A023400 A153637 A137618 * A021338 A021889 A309927

Adjacent sequences: A340863 A340864 A340865 * A340867 A340868 A340869

Keyword

nonn,cons

Author

Artur Jasinski, Jan 24 2021

Extensions

Corrected by Vaclav Kotesovec, Jan 25 2021

More digits from Vaclav Kotesovec, Jan 26 2021

Status

approved