An Archive of Curious Facts for the Curious
When I was a boy, my grandfather used to give me puzzles for me to solve. The following puzzle is one of them. A magic square is an arrangement of numbers from 1 to n2 in an n2 matrix in which each number should only occur once. Every row, column, and diagonal of a magic […]
Read MoreThe following is a simple activity for learning a simple number theory concept. This is based on the procedure described by Martin Gardner in Time Travel and Other Mathematical Bewilderments (1988). All you need for this is a pack of cards. First, remove all the cards of one suit (e.g. all the spades). Afterwards, arrange the […]
Read MoreConsider this group of squares: 1237892 + 5619452 + 6428642 – 2428682 – 7619432 – 3237872 = 0 When looking at the calculation above, it seems that it’s not a big deal. Although the six large squares yield zero after the calculation, it is not really that peculiar. But, try to remove the hundred thousands place or the left-most digit of […]
Read MoreSelect any whole number greater than zero then perform the following operation: If the number is even, divide it by 2. If the number is odd, multiply it by 3 and add 1. It’s said that if you continue to repeatedly apply the process, you’d always end up at 1. This is the premise of […]
Read MoreCurious Number 323323 Besides being a palindromic number, 323323 has some other cool properties. For example, it is equal to 7 × 11 × 13 × 17 × 19, which are consecutive primes. It’s also equal to the sum of consecutive numbers from 1 to 9 wherein each of the number is raised by a […]
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Here’s a site with a strange name (arguably, in this context, not so) that shows the first one million digits of π. The site is: http://3.141592653589793238462643383279502884197169399375105820974944592.com The exact web address that contains the one million digits of π is:
Read MoreI went to a math conference, and they had booths set up for several different branches of mathematics so students could learn about them. Unfortunately, the topology booth was closed, the algebra booth was way out in a field, and although I could get arbitrarily close to the analysis booth, I couldn’t touch it. The […]
Read MoreThis is a list I made quite some time ago. Might as well publish it here. 1. Even Galileo didn’t know calculus, so why should I? 2. When I tried to reach my textbook, I could only reach half the distance, then when I tried to reach it again, I could only reach half of […]
Read MoreThis numerical coincidence that I found is quite poetic. The way I see it, 20170 signifies the end of 2017. This is followed by a countdown which concludes with an exclamation welcoming 2018. Is this a sign of a good year ahead? Who knows. It’s difficult to rely on numbers to answer this kind of question. After […]
Read MoreLay out six matches in the way depicted in the illustration. The objective is to shift one match without displacing the others so that the resulting arrangement would represent an arithmetical fraction equal to 1. You are not allowed to move the match forming the horizontal fraction bar.
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