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2 Dec
2009
2 Dec
'09
11:02 a.m.
On Wed, Dec 2, 2009 at 6:33 PM,
is the third parentheses necessary ?
well, i guess you´re right, it´s not absolutely necessary because all the expressions have indizes, so one could guess all belong to the sum. but this way it´s clearly visible and formally precise that all expressions belong to the sum. Yes, true but a sum sign smaller than first parenthesis looks a bit strange . Anyway it' really my opinion. -- luigi