[ExI] Happy numbers - lucky, mersenne, kaprekar, narcissistic, …

[spike at rainier66.com]

COOL!  Thanks BillK!

<https://medium.com/predict/rockstar-numbers-of-math-lucky-mersenne-kaprekar-narcissistic-self-abundant-deficient-62829f9e9744>

I have discovered my own constant, but before I publish that, I must point out that I don't think it can be derived from any known mathematical process.  It can only be estimated by experiment.  More on that later.

spike