A215633 Decimal expansion of Sum_{n>=1} 1/n^(n^prime(n)).

1, 0, 0, 3, 9, 0, 6, 2, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1

Offset

1,4

Comments

Is this a finite sequence? (or equivalently, is this constant rational?)

Unlikely: the "apparent" rationality seems to be caused by the rapid growth of the denominators; one may instead speculate that the value is transcendental. - Joerg Arndt, Feb 05 2013

The constant is approximately 257/256 (see A021260).

Links

Table of n, a(n) for n=1..118.

Example

1.00390625000000000000000000... = 1 + 1/2^8 + 1/3^243 + 1/4^16384+...

Prog

(PARI) suminf(n=1, 1/n^(n^prime(n)))

Crossrefs

Cf. A062481.

Sequence in context: A267411 A370468 A021260 * A134878 A339097 A154540

Adjacent sequences: A215630 A215631 A215632 * A215634 A215635 A215636

Keyword

cons,nonn

Author

Balarka Sen, Aug 18 2012

Status

approved