0 points
All-in, let’s do base 210. Divisible by 2, 3, 5 and 7, covering all the small primes.
And we can do even better: base-420 which is also divisible by 4 and a funnier number.
3 points
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Because at some point the difficulty increases with regard to the number of symbols to memorize. A balance exists. I surmise it’s 12. Only 2 more to memorize than 10 and more ways to halve and double than 10. Easier for mental work.
1 point
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