You say just for fun, I wonder where is the fun if we start mining with our CPU 24/7 and never mine anything, could you provide some probability estimations on a single block found/time?
Yeah, doesn't sound fun... for educational purposes only? I'd prefer to mine some shitcoin using my CPU or GPU but with some real results/mining involved. Solo mining even on an Antminer S19 Pro is a lottery now already - 0.000065% chance of catching the block every 10 minutes (around 30 years to solo mine a block), CPU mining is not even a lottery, you're just losing money on electricity and burning out your CPU.

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