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The Leggett-Garg inequality attempts to classify experimental outcomes asarising from one of two possible classes of physical theories: those describedby macrorealism (which obey our intuition about how the macroscopic classicalworld behaves), and those that are not (e.g., quantum theory). The developmentof cloud-based quantum computing devices enables us to explore the limits ofmacrorealism in new regimes. In particular, here we take advantage of theproperties of the programmable nature of the IBM quantum experience to observethe violation of the Leggett-Garg inequality (in the form of a ``quantumwitness") as a function of the number of constituent systems (qubits), whilesimultaneously maximizing the `disconnectivity', a potential measure ofmacroscopicity, between constituents. Our results show that two-qubit andfour-qubit ``cat states" (which have large disconnectivity) are seen to violatethe inequality, and hence can be classified as nonmacrorealistic. In contrast,a six-qubit cat state does not violate the ``quantum-witness" beyond aso-called clumsy invasive-measurement bound, and thus is compatible with``clumsy macrorealism". As a comparison, we also consider un-entangled productstates with n = 2, 3, 4, and 6 qubits, in which the disconnectivity is low.

Experimental test of non-macrorealistic cat-states in the cloud