A372805 Decimal expansion of Sum_{k >= 1, 3|floor(k*log_10(2))} 1/3^k.

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

Offset

0,1

Links

Paolo Xausa, Table of n, a(n) for n = 0..10000

J. M. Borwein and P. B. Borwein, Strange Series and High Precision Fraud, The American Mathematical Monthly, Vol. 99, No. 7 (1992), pp. 622-640.

Formula

Approximately 3554/7381, correct to 49 digits: see Example 4.2 (d) in Borwein and Borwein (1992), p. 635.

Example

0.481506570925348868716976019509551551280314320552698762172...

Mathematica

First[RealDigits[Sum[If[Divisible[Floor[k*Log10[2]], 3], 1/3^k, 0], {k, 250}], 10, 100]]

Crossrefs

Cf. A000244.

Sequence in context: A254149 A021679 A197153 * A343058 A196618 A294830

Adjacent sequences: A372802 A372803 A372804 * A372806 A372807 A372808

Keyword

nonn,cons

Author

Paolo Xausa, May 13 2024

Status

approved