Archive for guests
Paul Nahin discusses his fabulous new book “Mrs Perkins Electric Quilt“, mosquitos, falling through the Earth, whether mathematics is “real” and much more!
Hmm. Somehow Stephen Morris pulls off that rarest of Math Factor tricks– leaving Kyle and Chaim at a loss for words, with his sneaky clock puzzle.
Oh by the way, would you like a cool Math Factor Poster? Click on this to download:
Man, what is it with puzzlers and prisoners? Jeff Yoak lines ‘em up and the stakes are high in this week’s puzzle.
Also, we are now twittering at MathFactor; each of the authors has an account of his own; mine is CGoodmanStrauss. You can tag solutions and comments with #mathfactor. See you there!
How can three people, each required to guess the color of hat on their head, strategize and maximize the chances they’ll all be right?
Jeff Yoak discusses the mathematical – and non-mathematical – nature of poker. Sitting at the table led him to wonder: Which numbers, precisely, are the sum of consecutive integers, and in how many ways?
The Math Factor podcast catches up with Jeff Yoak, an author on the Math Factor website, to discuss his fantastic Find-the-Gold-Coin puzzle.
David Singmaster, Puzzler Extraordinaire, early master of the Rubik’s Cube, poser of the Singmaster Conjecture, etc, etc, engages in some wordplay.
Rob Fathauer discusses the ins and outs of the mathematical toy business, and we ask: For which numbers is the sum of digits the same as the sum of digits of twice the number. For example:
The sum of the digits of 351 is 9 and the sum of the digits of 2 x 351 = 702 is also 9.
1) If a number has this property, can we always rearrange its digits and obtain another number with this property (513, 135, etc all have it)
2) Which powers of 2 have this property?
3) And most of all, can you give a simple characterization of the numbers with this property, in terms of just the digits themselves?