  We propose a novel framework for off-chain execution and verification of
computationally-intensive smart contracts. Our framework is the first solution
that avoids duplication of computing effort across multiple contractors, does
not require trusted execution environments, supports computations that do not
have deterministic results, and supports general-purpose computations written
in a high-level language. Our experiments reveal that some intensive
applications may require as much as 141 million gas, approximately 71x more
than the current block gas limit for computation in Ethereum today, and can be
avoided by utilizing the proposed framework.
