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> Numbers (1)> Games> Paradoxes> Riddles (1)
> Just Math (2)> Science> Algorithms
The largest palindrome expressable as a product of two 2-digit numbers is 9009 = 91 × 99.

What is the largest palindrome that is a product of two 3-digit numbers?

Source: Project Euler.

(No Solution Yet, 1 Comments) Submitted on 2015-04-27 by Ady TZIDON   
Difficulty: 4 of 5 Bonus: The Amazing Stamp (in Geometry) Rating: 4.45
You have an ink stamp that is so amazingly precise that, when inked and pressed down on the plane, it makes every circle whose radius is an irrational number (centered at the center of the stamp) black.

Is it possible to use the stamp three times and make every point in the plane black?

If it is possible, where would you center the three stamps?
(Solution Posted, 45 Comments) Submitted on 2003-12-01 by DJ   
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