I sent etherium to a one letter wrong address I typed 6 instead of a b amongst those letters from my mining account. I would like to know what can I do to recover those etheriums?
Nothing. It's gone. Always, always copy and paste addresses. Then, verify it's the same address when pasted (check first few and last few characters), because there exists in the wild malware that will surreptitiously change addresses on the clipboard to another address.
This is the process I follow, since I use multiple currencies:
- Verify the source and destination wallets/exchanges/whatever are the same currency.
- Copy and past the address
- Verify the address is the same in the source and destination
- Double-check 1-3
You're are dealing with (more-or-less) real money, so you have to be careful. For large amounts -- send a small test transfer and wait for it before continuing with the larger amount.