A201505 - OEIS

A201505

Decimal expansion of cos(1/2).

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

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OFFSET

0,1

COMMENTS

By the Lindemann-Weierstrass theorem, this constant is transcendental. - Charles R Greathouse IV, May 13 2019

LINKS

Table of n, a(n) for n=0..83.

Index entries for transcendental numbers

FORMULA

Taylor series representation: 1 -1/(2^2*2!) +1/(2^4*4!) -1/(2^6*6!) -...

EXAMPLE

0.877582561890372716... = sqrt((1+A049470)/2) = sqrt(1-A201504^2).