A237192 Decimal expansion of 2^i + 2^(-i), where i = sqrt(-1).

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

Offset

1,2

Comments

Approximately equals 1/2*(1+2^(2/3))*2^(1/4) = 1.538477870...

Links

Table of n, a(n) for n=1..83.

Formula

Equals 2*cos(log(2)). [Bruno Berselli, Feb 05 2014]

Example

1.53847780272794425315665998732254140288179198982392770633974301485816...

Mathematica

RealDigits[ Chop[ N[ 2^I + 2^(-I), 111], 10^-110], 10, 111]

Crossrefs

Cf. A237193.

Sequence in context: A021654 A021069 A372269 * A161488 A010484 A174930

Adjacent sequences: A237189 A237190 A237191 * A237193 A237194 A237195

Keyword

nonn,cons,easy

Author

Robert G. Wilson v, Feb 04 2014

Status

approved