Comment by Jtarii
9 hours ago
>People used to memorize log and trig tables, and no one would say that's part of being a competent mathematician at this point.
That would be closer to engineering or accounting than mathematics. I don't think mathematicians do much arithmetic at all.
Go read the story that Richard Feynman tells of betting an abacus user. He used his knowledge of some strange numbers. It's in _Surely You Must Be Joking_.
I suspect his facility with numbers and his knowledge of tables like this really helped him do physics research.
See also his stories on approximation.