Formula for sum of 1 to 75 ?

[auto.pilot]

Example: I have the number 75 in a cell. The sum of 1, 2, 3..to 75 is 2,850. What formula would give this result?

thanks

jim

 

[kpark91]

n * (n + 1) / 2

where n is the number of elements.

this formula only works from 1 to n.

 

[auto.pilot]

Thanks!