challenge for programmable calculators

[kakima]

I tried exactly that earlier today. Unfortunately there aren't too many other solutions, at least for bases 10 and 16, until you go beyond eight digits. (I'm not saying there are solutions beyond eight digits, just that I stopped there.)

My original thought was to propose a challenge to write a program that given a number N, searches for N-digit solutions. When I wrote just such a program and put it in a loop from two to eight, it found only the two known 3-digit solutions. For base 16, it only found one solution.

There may be solutions in other bases. I suppose I'll have to try them...