Assume you want to add up

5/1! +( 5^2)/2! + (5^3)/3! + (5^4)/4!

use

=SUMPRODUCT(5^(ROW(1:4))/FACT(ROW(1:4)))

follow evaluate formula and watch how the calculation works - that will help

Modify to suit your needs
--
Wag more, bark less


"arithmatical and geometrical series" wrote:

Hi there , i've a question , how can i do a geometrical or arithmetical
progression in one function at one cell in excel as example
this series ˆ‘_(i=0)^n–’〖xi〗^2 ˆ¶xi=x(i-1)+ 1

and other similar series and that function request x when i = o and n
and thanks