When I was 10 years old (5th grade), circa 1963, I thought I might have discovered some new principle of numbers, but it was almost impossible for me to find out. There was no one to ask, and no references I could find.
My father would take me to his office (attached to a flour milling operation) on the weekend to give my mother a break, and there I would wander around entertaining myself by admiring the sailfish mounted on one man’s wall, and the manual plug-in switchboard. There were, of course, many desks in an open area for clerical work, and many of those desks had calculators.