Those continuing adventures of Bitcoin – revisited

Bitcoin mining is bad for the environment: https://medium.com/@grist/bitcoin-could-cost-us-our-clean-energy-future-3564d8ecba82 And what are exactly those mathematical problems, that the mining computers work on, and which require lots of electricity: Here is a relatively simple explanation: Comment from discussion waxwing’s comment from discussion "What is it exactly that miners work on? Why does it generate bitcoin?".