Post #652749

Additions with unique digits: A tale of puzzling and AI The other day, Markus Krötzsch and I were catching up when one of his kids came in. She told us about a puzzle her math teacher gave her: How many integer sums are there where the equation uses each digit at most once? The simplest example is 1+2=3, but 12+47=59 also works. On the other hand, 1+9=10 isn’t a solution because the digit ‘1’ appears twice (in the first number and the sum). 1/19