References:

  1. Inder J. Taneja, Single Digits Representations of Numbers from 1 to 20000,  https://inderjtaneja.com/2019/01/01/single-letter-representations-of-numbers-from-1-to-20000/
  2. Crazy Representations of Natural Numbers – The 10958 Problem
  3. Crazy Representations of Natural Numbers Using Factorial From 200001 to 300000
  4. Inder J. Taneja, Same Digits Equality Expressions: Power and Plus, Zenodo, January 03, 1-1729,  https://doi.org/10.5281/zenodo.3597506.