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| Fun and games. Photo: Dean Mouhtaropoulos/Getty Images Europe |
For math geeks like me, 2018 was a banner year: not only was it a year in which the field’s top prize was awarded, it was the only year in this century featuring days lining up with both the Golden ratio, an elegant proportion found throughout art and nature, and the mathematical constant e, which is at
the core of calculus.
But the mathematician in me also can’t help but note that the number 2,018 has some ominous properties: It’s deficient, meaning that the sum of all its positive divisors is less than itself. And it’s also odious, meaning that it has an odd number of ones in its binary expansion, 11111100010. 1
This year is pretty cryptic, as well -- it features prominently in the first of the three Beale ciphers, an 1880s cryptographic puzzle that supposedly describes the location of a multimillion-dollar treasure. (Hint: check the cipher’s second line.)
And 2,018 is a crystallogen number, giving it a property derived from chemistry that means it’s slightly unbalanced: atoms with full shells containing 2,022 electrons are electronically stable. But 2,018? It’s, well, just a few short. (Maybe three years from now will be less volatile?)...
And 1,009 is happy, meaning that if you take the sum of the squares of its digits, and then take the sum of the squares of the digits of the result, and so forth, you eventually get to 1. It’s also lucky, which means that it survives the following curious elimination process: Start with the odd numbers, note the second-largest is three; and delete every third number. The third-largest number remaining is then seven, so now delete every seventh. The fourth-largest is then nine, so delete every ninth, and so on.
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Source: Bloomberg
