A356023 Decimal expansion of Sum_{j>=1} 2^^j/2^^(j+1) where ^^ indicates tetration.

7, 5, 0, 2, 4, 4, 1, 4, 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

Offset

0,1

Comments

This series converges quickly and a very good approximation of this constant is given by the first three terms, 2/2^2 + 2^2/2^2^2 + 2^2^2/2^2^2^2 = 3073/4096, since the next term 2^2^2^2/2^2^2^2^2 is about 1/10^19723.4853.

Links

Table of n, a(n) for n=0..86.

Example

0.750244140625...

Mathematica

RealDigits[Total[Most[(s = NestList[2^# &, 2, 4])]/Rest[s]], 10, 100][[1]] (* Amiram Eldar, Jul 23 2022 *)

Crossrefs

Cf. A356022.

Sequence in context: A277067 A354823 A241902 * A113223 A096414 A144923

Adjacent sequences: A356020 A356021 A356022 * A356024 A356025 A356026

Keyword

nonn,cons

Author

Marco Ripà, Jul 23 2022

Status

approved