sum and maxima



Hello

It seems that maxima have some problems to calculate sums that maple do. 
For instance :
ev(sum(binomial(n,k),k,1,n),simpsum); 
return nothing. Maple return n*2^n/2.
Is it possible to help maxima to do this calculation ?

Best regards
-- 
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Michel Gosse
michel.gosse@ac-poitiers.fr
Clef pgp disponible sur 
http://www.keyserver.net/en/
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