(summand, index of summation, lower index of summation, upper
index of summation).Summation
Press MENU 9 to access the CAS menu, press 2 to access the CALC menu, then press 4 to select 4:S. One can then evaluate summations. Apply the syntax
(summand, index of summation, lower index of summation, upper
index of summation).
For
example, to evaluate 
,
after S( is pasted in the entry line, enter
X X2 , X , 1 , 1 0 ) EXE
One
may also use the alpha key to enter the index as i or k as used more often in
summation notation. For example, to compute the sum of k2 as
k goes from 1 to 10, first select 4: from the CALC menu. Then,
after ( is pasted in the entry line, enter
ALPHA K ^ 2 , ALPHA K , 1 , 1 0 ) EXE
To
evaluate 
,
after ( is pasted in the entry line, enter
ALPHA K ^ 2 , ALPHA K , 1 , ALPHA N ) EXE
The
Casio can evaluate some basic infinite series, such as a geometric series; for
example, 
.
After ( is pasted in the entry line, enter
. 3 ^ X , X , 1 , OPTN F1 ) EXE