  A test of quantumness is a protocol where a classical user issues challenges
to a quantum device to determine if it exhibits non-classical behavior, under
certain cryptographic assumptions. Recent attempts to implement such tests on
current quantum computers rely on either interactive challenges with efficient
verification, or non-interactive challenges with inefficient (exponential time)
verification. In this paper, we execute an efficient non-interactive test of
quantumness on an ion-trap quantum computer. Our results significantly exceed
the bound for a classical device's success.
