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A237193
Decimal expansion of 3^i + 3^(-i), where i = sqrt(-1).
1
9, 0, 9, 6, 6, 4, 8, 4, 5, 6, 5, 3, 2, 1, 9, 5, 1, 0, 0, 5, 5, 1, 3, 0, 2, 8, 7, 1, 9, 0, 0, 8, 4, 9, 6, 8, 1, 7, 6, 3, 8, 0, 3, 3, 8, 5, 4, 9, 1, 3, 9, 6, 6, 3, 0, 2, 2, 5, 2, 0, 4, 2, 2, 8, 5, 2, 3, 8, 4, 7, 0, 3, 4, 4, 4, 7, 7, 2, 0, 0, 3, 8, 9, 3, 2
OFFSET
0,1
COMMENTS
Approximately equals 1/log(3) = 0.9102... or 23/(15^(1/2)+4^(2/3))^(1/2) = 0.909664848... .
FORMULA
Equals 2*cos(log(3)). [Bruno Berselli, Feb 05 2014]
EXAMPLE
0.909664845653219510055130287190084968176380338549139663022520422852...
MATHEMATICA
RealDigits[ Chop[ N[ 3^I + 3^(-I), 111], 10^-110], 10, 111]
CROSSREFS
Cf. A237192.
Sequence in context: A160576 A104756 A154994 * A132268 A252851 A241290
KEYWORD
nonn,cons,easy
AUTHOR
Robert G. Wilson v, Feb 04 2014
STATUS
approved