CTK Insights

This is just to document a few simple math and logic activities recently added to the Interactive Mathematics Miscellany and Puzzles site. Filling a Grid with Good Neighbors There is a number of chips placed in the squares of an N×N grid. We can add a chip to a square, provided it has at least [...]

Here is a problem from an old Russian collection of problems offered at an evening math school. At the time - now, about 50 years ago - I have not seen anything strange about it. Now I do. Does it come with age? Here's the problem: A Math Circle has 31 participant. Their ages are [...]

John Sharp did this again. He sent me a link to a curious piece of information. Nearly a century ago, German physicist Woldemar Voigt discovered strange phenomenon in iron pyrite crystals (also known as Fool's Gold). His research suggested that the crystals somehow grew thicker when stretched. Voigt could not explain the strange behavior (he [...]

Until very recently my interest in tessellations was rather utilitarian. I could not help but admire the proofs of the Pythagorean and Napoleon's theorems that used tessellations. I have also illustrated in Java how a certain kind of a hexagon that M. C. Escher mentioned in his notebooks tessellates the plane and the same property [...]

A recent book Loving + Hating Mathematics by Reuben Hersh and Vera John-Steiner is a collection of stories and anecdotes about mathematcis and mathematicians. The stories have a purpose - to demonstrate that mathematics is a human endeavor and that mathematicians are as human as the next man. Some stories show the emergence of the [...]