A388335 Decimal expansion of 4 * exp(-2*Pi/3).

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

Offset

0,1

Links

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

Simon Plouffe, Numbers in the base e^Pi, 2025.

Formula

Empirical: Equals Sum_{k>=0} A022611(k) / exp(k*Pi).

Example

0.49257884428053253456613459891468607246...

Mathematica

First[RealDigits[4*Exp[(-2*Pi)/3], 10, 100]]

Prog

(PARI) 4 * exp(-2/3 * Pi)

Crossrefs

Cf. A022611.

Sequence in context: A388445 A021071 A197146 * A021207 A200094 A277526

Adjacent sequences: A388332 A388333 A388334 * A388336 A388337 A388338

Keyword

nonn,cons

Author

Simon Plouffe, Sep 15 2025

Status

approved