Points for being different, but this solution doesn't work because binary OR is not the same as ADD for all inputs. This shows the importance of good testing code. I assume it passed the testing that was available at the time.

Thanks for this solution. I learned more about functional programming by studying it and getting a very nice piecewise explanation by Claude, the AI Chatbot. Since I'm not very familiar with this style, I tested this solution and found that it fails with a time-out at 12 seconds every time, which makes me wonder how it got on this list, except I'm glad it did. Buddy() is written to call sum(i) again if i<sum(i). If the sum(i) is saved and reused (oh no!), about 25% of the time is saved and the solution passes "ATTEMT" most of the time in 10-11.5 seconds. The solution with 12 or more votes for Best Practices, finishes in 2-3 seconds. Cheers.

I had that thought too. But n has a fixed range and while m may be larger than the limit of the range, there are only a limited number of m's, one for one with the values of n.