A388516 Decimal expansion of 2 * exp(-Pi / 4) * sqrt(2).

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

Offset

1,2

Links

Table of n, a(n) for n=1..87.

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

Index entries for transcendental numbers.

Formula

Empirical: Equals Sum_{k>=0} A112150(k) / exp(k*Pi).

Example

1.28958776777933779700946773824051783935116121370143941564420114603521802540....

Mathematica

First[RealDigits[2*Sqrt[2]*Exp[-1/4*Pi], 10, 100]]

Prog

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

Crossrefs

Cf. A112150.

Sequence in context: A388191 A340778 A108744 * A388346 A195724 A081819

Adjacent sequences: A388513 A388514 A388515 * A388517 A388518 A388519

Keyword

nonn,cons

Author

Simon Plouffe, Sep 17 2025

Status

approved