Mathemagician Video

[EdS2]

Thanks for that Steve - last year I was looking everywhere for it, and didn't find it. There are many accounts of child prodigies and mental calculation, but I didn't find one quite so colourful.

This was one source, Mathematical Recreations and Essays, by W. W. Rouse Ball. The first edition is from 1892, the fourth, which is easy to find, is from 1905, but it turned out that I needed the ninth edition, from 1920. The bit I was searching is a chapter on Calculating Prodigies, and there's much of interest there. Here it is, starting on page 248:
https://archive.org/details/mathematical...8/mode/1up

[Allen]

(07-19-2021 03:27 PM)rprosperi Wrote:  Interesting and entertaining video:

https://www.flixxy.com/lightning-calcula...-magic.htm

I have his Great Courses Video and corresponding book where his mnemonics are described. It's very interesting, but takes considerable practice to master. He has some very clever ways of storing intermediate values for his calculations.

I was studying his book when I went in for a routine surgery some years ago, and apparently (I remember only blurry pieces of this conversation) as I came out of anesthesia I was asking the nurses to give me a two digit number to square in my head. They were not impressed or amused about me delaying my discharge paperwork to wander around the ward looking for a calculator to race against.

I probably would have lost anyway..