The above 4 × 4 magic square only has the digits 2, 0. 1, and 9 (from the year 2019) and as a bonus, the four digits in its upper-left section form “2019”. It has a magic sum of 132. This means the sums of the magic square’s columns, rows, and diagonals are all equal […]

The difference between two consecutive primes is called prime gap. Prime gaps are always even except for the prime gap between 2 (the first prime and the only even prime) and 3 (the first odd prime), which is 1. At first, prime gaps are small. As the primes get bigger, larger prime gaps start to […]

Solomon Lefschetz During the mid-1930s, when the Institute of Advanced Study and the Princeton’s Fine Hall were still sharing the same area, they had a thing called the “Princeton Scale of Obviousness”. The scales were as follows: If Joseph Wedderburn says it’s obvious, everyone in the class had noticed it ten minutes ago. If Frederic […]

1. The Origin of the Song The origin of “The Twelve Days of Christmas” is ambiguous. Evidence suggests that it originated from France and three French versions are known. The earliest English version appeared in a 1780 book titled Mirth Without Mischief under the heading “The Twelve Days of Christmas sung at King Pepin’s Ball”. […]

Several non-mathematicians were asked to identify all the prime numbers between 1 to 100. Psychologist: 2 is prime, 3 is prime, 5 is prime, 7 is prime and 9 is prime as well though it tries to suppress it. Philosopher: I don’t really know the answer to that, but I’m glad that we can have […]

This is a part of the lost articles I wrote on GeoCities in 2003 (Yes, it’s been fifteen years!). Those were the times when I had nothing else better to do. Unfortunately, I can’t find the original articles no matter how hard I searched through my old files. My page was also not archived by […]

Little Johnny is not so little anymore. So, now, it’s time for him to learn some algebra. Johnny’s math teacher was bemused over the answer to an exam question about right triangles that he had written. It was the single word “rhinoceros.” “Well,” the teacher said, “This is not a word that I ordinarily associate […]

In March 24, 1983, the New York Times published the following interview with mathematician Robert Langlands (1936- ): Q: What does a theoretical mathematician do? A: You mean what does he do or why does he do it? Q: What is your aim, your goal? A: Let me think a minute before I answer that question. Are you asking, […]

A biochemist is cultivating living cells. Each cell splits into two cells after one minute. One minute later the two cells split to make four, then the four become eight, and so on. Every minute the number of cells doubles. Assume that it takes an hour for one cell to grow until a bottle is filled. If the chemist […]

Here is a classic puzzle. Say that you have two hourglasses of different sizes. The bigger hourglass runs for 11 minutes while the smaller one runs for 7 minutes. Using these two hourglasses, how can you measure 15 minutes exactly.?