A356869 - OEIS

A356869

Decimal expansion of 4 / sqrt(5).

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

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OFFSET

1,2

COMMENTS

The area of a golden rectangle inscribed in a unit circle.

The width and height of the rectangle are:

W = sqrt(2 - 2 / sqrt(5)) = A179290.

H = sqrt(2 + 2 / sqrt(5)) = A121570.

LINKS

Table of n, a(n) for n=1..97.

FORMULA

Equals [1; 1, 3, 1, 2] (periodic continued fraction expansion). - Peter Luschny, Sep 02 2022