Sum
The addition of two numbers gives a sum
factor + factor = sum
Explanation
You can add several numbers, and also infinitely many numbers. With the sigma symbol you write it as
∑ = 1 + 2 + 3 + 4 + 5 + ···
An integral is even the sum of an infinite number of infinitely small quantities. With the sum sign you can write that as
∫ v du
Example 1
Goldbach's conjecture says something about the sum of prime numbers, such as
10 = 3 + 7 = 5 + 5