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Consider this nested array
[[1,2,4],[1,2,3],[2,3]]
In each subarray in which 1 appears, a 2 appears. You might say that 1's presence is dependent on 2's presence.
The converse is not true, as 2 appears in a subarray without 1.
Additionally, 3 is dependent on 2, and 4 is dependent on 1 and 2.
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