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This is an interesting group of functions that may be of use for students
studying discrete functions and sequences.
ITERATE(expression,var.name,strt,num.iter.)
This function evaluates an expression a specified number of times, starting
with a supplied initial value an using the answer to the previous evaluation as
the value for the variable in the next evaluation.
Eg. ITERATE(X
2
-1,X,2,5) gives an answer of 15745023
This answer is obtained as follows:
initial value: X=2 first iteration
2
1x − = 3
new value: X=3 second iteration
2
1x − = 8
new value X=8 third iteration
2
1x − = 63
new value X=63 fourth iteration
2
1x − = 3968
new value X=3968 fifth iteration
2
1x − = 15745023
Final answer: X = 15 745 023