Frequently in mathematical literature a short notation for sums is used which involves the Greek capital letter sigma, written  In this notation,

is written as

and the auxiliary variable i is called the index of summation. Thus, for example,

Under the capital sigma, one indicates the symbol that is used as the index of summation and the initial value of this index. Above the sigma, one indicates the final value. The general polynomial of degree n can be written as

 

Monday, June 22, 1998