I enjoyed the column! It is clear that with your final “intriguing sum”, you were hoping that the readers would notice that the sum is again 10,000. But beyond that, you undoubtedly hoped to stir our curiosity as to why the sum is identical. And it certainly worked for me. As soon as I noticed the identical results, I immediately saw that the second series could be transformed to the earlier series by a simple pairing of the numbers. But I’ll say no more, leaving it to other readers to fill in the details!