357686312646216567629137 and Friends

Many people close to FWPhys are aware of, in possession of, or about to possess, our first STEM merchandise, the Left Truncatable Prime Pencil. Printed on it is the largest base-10 number that remains prime as you remove digits from the left side by means of sharpening the pencil. US$3 a pair. It's common knowledge … Continue reading 357686312646216567629137 and Friends

All Legal combinations of digits For the 24 Game

The rules of our 24 game are based on the original card game, and quite simple: Take 4 integers between 0 and 9, and by joining them with parentheses () and the 4 arithmetic symbols (+,-,×,÷) only, formulate an equation that gives 24. My mother and I used to compete and see who could work … Continue reading All Legal combinations of digits For the 24 Game