Got another one

I don't usually have enough time to invest a few hours in solving the Monday Math Madness puzzles on Wild About Math and Blinkdagger, but twice so far (out of the five puzzles posted) I was able to see how to do the puzzle essentially as soon as I read it, and so sent in an entry.

As with the first time, my entry was again correct, but still no banana, unfortunately. (It was essentially to prove that 1 and 9 were the only squares with no even digits.)

I'm there in the list of people giving correct answers, under the longer version of my nom-de-blog.