arithmetic
posted by Joe .
What is the sum of the arithmetic sequence 22, 13, 4 … if there are 28 terms?

The distance is 9, first term 22
Isn't there a formula for this?
posted by Joe .
What is the sum of the arithmetic sequence 22, 13, 4 … if there are 28 terms?
The distance is 9, first term 22
Isn't there a formula for this?