https://doi.org/10.4169/college.math.j.46.3.172 https://www.jstor.org/stable/10.4169/college.math.j.46.3.172 The College Mathematics Journal emphasizes the first two ...
I have found a 3-digit perfect square, a 3-digit perfect cube and a 4-digit triangular number that between them use 10 different digits, with no leading zero. (Triangular numbers are those that fit ...