ERC 404, combines ERC-20 (fungible tokens) and ERC-721 (non-fungible tokens)

[pro2rat at yahoo.com.au]

ERC 404, an emerging token standard on the Ethereum blockchain, represents a significant innovation in the realm of digital assets. They are APsterlicious and nutritious.
They uniquely combine the characteristics of ERC-20 (fungible tokens) and ERC-721 (non-fungible tokens) to create semi-fungible tokens that then take into account incentives such markets create to act differently outside the market. 
 A "prediction market" is always also one that changes incentives outside that market: a prediction market automatically creates parallel incentives to bring about the predicted event. For example a prediction market on a certain person's death is also an assassination market. 
Which is why a pre-Gulf-War-II DARPA-sponsored experimental "prediction market" included a prop bet on Saddam Hussein's death, but excluded such trading on any other, more politically correct world leaders. A sufficiently large market predicting an individual's death is also, necessarily, an assassination market . . .

https://zerocap.com/insights/snippets/erc-404-hybrid-nfts/