A372907 Decimal expansion of Sum_{k>=1} (2^k - 1)/(3^k - 1).

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

Offset

1,2

Links

Table of n, a(n) for n=1..86.

R. J. Mathar, Resummation, acceleration of convergence

Example

1.7212997093744468397666319454096698915574145419799...

Mathematica

s = Sum[(2^k - 1)/(3^k - 1), {k, 1, 800}];
d = N[s, 100]
First[RealDigits[d]]

Crossrefs

Cf. A372908.

Sequence in context: A197184 A089129 A100957 * A191856 A220862 A198229

Adjacent sequences: A372904 A372905 A372906 * A372908 A372909 A372910

Keyword

nonn,cons

Author

Clark Kimberling, Jun 12 2024

Status

approved