Monthly Archives: August 2006

Sums, differences, and surprises

I’ve received the following note from Barry Cipra, bit-player’s Bureau Chief in Northfield, Minnesota, (where all hail broke loose yesterday): Your latest postings [here and here] have motivated me to idle away some time with a variant of the problem(s) … Continue reading

Posted in mathematics, problems and puzzles | 1 Comment

More on sums and differences

Kevin O’Bryant, whose work on sets that have more sums than differences was mentioned in this recent post, writes as follows: Here’s a related problem that Mel Nathanson and myself (with Ruzsa and a few students) have also been thinking … Continue reading

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Counting sums and differences

Take a set of integers, say {0, 2, 5, 8, 11}, and write down all the numbers that can be represented as sums of two elements drawn from this set. For our example the answer is {0, 2, 4, 5, … Continue reading

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Conspiracy theories

The new issue (September-October) of American Scientist is available on the Web, and subscribers to the ink-and-paper edition should receive copies soon. My “Computing Science” column is more topical than I would like, given today’s headlines. I examine some ideas … Continue reading

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Haµte cuisine

I can cook anything, as long as the recipe starts with “Take it out of the freezer” and ends with “Put it in the microwave.” Go ahead and scoff, but I’m proud of my culinary accomplishments. Furthermore, I submit that … Continue reading

Posted in modern life, physics | 2 Comments

The figure in the flagstone

The banner image at the top of this page might be taken for an algorithmic attempt to imitate a fern, although in my opinion the pattern bears a closer resemblance to the two-dimensional corals known as sea fans, or gorgonians. … Continue reading

Posted in science | 2 Comments

Beach reading

A few years ago Michael Berry revealed that his first choice in reading matter, if he were stranded on a desert island, would be Abramowitz and Stegun, also known as Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, … Continue reading

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