thanks for your answer! Yes, I had already understood that. I would like to see the last "task" to "solve", just out of interest. Is it officially available? Do you know?
Discussion
Just take a suitable set of unconfirmed tx's from the mempool, the hash of the last block, add random number (a nonce) and hash it!
If the result has enough leading zeros, you win! If not just change the nonce and try again!