BUILT-IN MATHEMATICA SYMBOL
BlankSequence 
(two 
characters) or BlankSequence[]
is a pattern object that can stand for any sequence of one or more Mathematica expressions.
or BlankSequence[h]
can stand for any sequence of one or more expressions, all of which have head h.
A function definition that works with any nonzero number of arguments:
| Out[2]= |  |
A function definition that works with any nonzero number of real arguments:
| Out[2]= |  |
A function definition for a symbol followed by any nonzero number of integer arguments:
| Out[2]= |  |
New in 1
