From 1 to 100, what is the result?

From 1 to 100, what is the result?

So (1 + 100) * 100 / 2 = 5050 (x0d1 + 2 + 3 + 4 + 5 + 6 add to 100 (x0d100 + 99 + 98 + 97 + 96 + 95 add to 11 + 100 = 101, x0d2 + 99 = 101, x0d3 + 98 = 101, x0d4 + 97 = 101, x0d4 + 97 = 101, x0d5 + 96