Re: [math-fun] Computational effort

Separating U235 from U238 is a pretty decent "proof of work" system. "Uraniumcoin" ? "Isotopecoin" ? "Hexofluorocoin" ? "Centricoin" ? These "coins" put the "rich" into "enriched"... https://en.wikipedia.org/wiki/Enriched_uranium Of course, you may only want to use Oralloy certificates in commerce, exchangeable* for the real thing. Who wants to carry around a lead wallet, with even heavier contents? * (Except by certain not-so-friendly countries.) At 07:16 AM 3/20/2015, James Propp wrote:

(b) the Manhattan Project,