Question: An arithmetic progression is a sequence of numbers in which the distance (or difference) between any two successive numbers if the same.
This in the sequence 1, 3, 5, 7, ... , the distance is two while in the sequence 6, 12, 18, 24, ... , the distance is 6. Given the positive integer distance and the positive integer n , related the variable  sum with the sum of the elements of the arithmetic progression from 1 to n with distance .
For case, if distance is 2 and n is 10, then sum would be linked with 25 because 1+3+5+7+9 = 25 .
You have to show the sum of the elements of the arithmetic progression.