The puzzle is as follows: Suppose you have a three-digit number in the octal system. If you add or subtract 212 (also in the octal system) from that initial number, you get a three-digit palindromic number in the same system. Using this information. How many numbers will follow that peculiar rul...

My home is the air, the earth, and the sea, Between highs and lows you are sure to find me. I am boisterous and loud, as bright as the sun, But those who can see me or hear me are none. I am born with a goal, I live in a shell, I accompany those who greet and farewell. I have numerous forms, inte...

In this puzzle, create $x$ to Maximize $\dfrac{e\pi}{x}$ where $x \ge e\pi$. To create $x$ you must use less than $23\le e^\pi\simeq 23.14$ digits and operators from: $0,1,2,3,4,5,6,7,8,9$ $+\quad-\quad/\quad\times\quad$ dot $.$ $\quad($ $\quad)$ For instance, if I decide to choose $x = 3.14159...

This is an infinite cryptic crossword. Solve the clues and use the four given grid pieces (each duplicated infinity times) to create a grid that continues endlessly in all directions. Across A1. Soldier that earns pay from sea in Ajaccio, Corsica's capital A3. Crazed maniac? Her rant shows extre...

My infix will give you a name My suffix will help you with pain My prefix will make you frown My whole will let you down What am I?

An entry in Fortnightly Topic Challenge #47: "Wacky Sudokus" Other puzzles in this series Welcome to the seventh puzzle in this series! For more information about the series, see the first puzzle and the introduction. Enjoy! Halway through now! The puzzles so far have been somewhat of an introd...

I guess I'm French tall and strong. winds come and go, though they cannot blow me over. people buy me and sell me an I am very common on the street and roads but they rarely build me without help my rival is short compared to me take me apart, and you've got me cornered I may have a tail, dependi...