A video that explains only the basics of Blokchain technology.
For more advanced topics you may want to check:
Towards Imandra Contracts: Formal verification for Ethereum, by Grant Passmore (of Aesthetic Integration)
Imandra Contracts Formal Verification for Ethereum, by Grant Passmore (Aesthetic Integration)
Language: OCaml
Year 2015.
Languages/tools: OCaml, Imandra, IML
Year 2016.