Not exactly correct. If all of the bits is 1, then the value is possibly in the set (not "probably", but "possibly", with the likelihood being affected by the sizes of the set and the array).
If any of the bits is zero, the value definitely isn't in the set (also not "probably haven't", but definitely not).
Was trying to keep the initial explanation simple by leaving out the false positives scaling relative to the size of the array and set, and then clarifying at the end.
The second part (any 0 bits it hasn’t been seen) is true, a goof up on my part.
If any of the bits is zero, the value definitely isn't in the set (also not "probably haven't", but definitely not).