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I was wondering if the constant

[tex]

\sum_{n=1}^\infty{2^{-2^n}}

[/tex]

has a certain name or some history or anything. It certainly appears not to have a closed form expression. It also certainly has some value because it's majorized by the simple geometric series. It's numerical value is 0.31642150902189314371 (given by http://www.research.att.com/~njas/sequences/A078585" [Broken], but is there anything else known about it?

Regards,

Pere

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# A constant without name?

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