\cdots
Ellipsis for indicating continuation or omission in mathematical expressions or text.
Indicating a sequence of numbers.
1, 2, 3, \cdots, n
Summation of a series.
a_1 + a_2 + a_3 + \cdots + a_n
List of variables or elements.
x_1, x_2, x_3, \cdots, x_n