Determine the value of $(101 \times 99)$ - $(102 \times 98)$ + $(103 \times 97)$ − $(104 \times 96)$ + ... ... + $(149 \times 51)$ − $(150 \times 50)$.
Problem
Source: OMK 2018 Sulong, Section A Problem 5
Tags: number theory, contests, Perfect Squares, difference of squares