Little progress had been made in solving Ramsey problems since the 1930s. Now, researchers have found the answer to r(4,t), a longstanding Ramsey problem that has perplexed the math world for decades.

An elementary math problem has divided the internet after an easy-looking equation turned out to be anything but simple. Many X users were stumped by the problem 16 ÷ 4 X 4 - 4, posted by ...