Bitcoin: A Peer-to-Peer Electronic Cash System
4. Proof-of-Work To implement a distributed timestamp server on a peer-to-peer basis, we will need to use a proofof-work system similar to Adam Back's Hashcash [6], rather than newspaper or Usenet posts. The proof-of-work involves scanning for a value that when hashed, such as with SHA-256, the hash begins with a number of zero bits. The average work required is exponential in the number of zero bits required and can be verified by executing a single hash.
Here it does not say that Satoshi used Adam back's Hashcash but it is similar to Adam Back's Hashcash. Now who implemented the Bitcoin in the Blockchain and started to mine Bitcoin ?
Does Adam Back has any proof that he imagined the Hashcash Proof-of-Work in 1997 ? Where did he propose the Hashcash ? B-Money of alleged Wei Dai, Where did he published back in 1998 ? what proof does he got ? Bit+Gold=Bitgold; Bitgold of alleged Nick Szabo, Where did he published as proof of existence ? He predated it to looklike the precursor to Bitcoin. Infact, Bitcoin, B-Money, Bitgold, Proof-of-Work, Bitrica, Bitmohar, ZCash, Ethereum, Litecoin, IXCoin, Infogami, Intersango, Clicme, UNCC, CoinDesk, Cointelegraph, BitcoinFX, Liberty Reserve, UNFDIC, and E-Gold and E-cash are the ptotypes projects of Digital Electronic Cash System conceived by Satioshi Nakamoto the invisible visionary SI347. He started his research work from 1984 and formulated the E-Cash in 1994. In 1994 one of his Single Currency project were hijacked by an EU economist that led the EU single currency Euro come in to existence in 1999. Finally Satoshi Nakamoto changed his project plan and paradigm and created Bitcoin and Blockchain in May 2007. 1 currency now.