Sorry if it's dumb, but my reading of sequester (PHB, 274) suggests that it prevents any locate X spell (target) from detecting the target, as well as scrying (PHB, 273) and clairvoyance (PHB, 222) since these both create divination sensors, but wouldn't prevent the target from being visible to a creature using see invisibility (PHB, 274) since it doesn't target the hidden object/creature.
It might feel a bit weird, but remember it's only possible if you accurately deduce the room or location of the sequester'd item, being impossible to find it if someone cast sequester and hid it/never came back for it (so nobody could track it and deduce its location).
Can you use dispel magic (PHB, 234) and target "the closest object in range under the effect of sequester"? If not, what if you cast detect magic (PHB, 231) and then cast dispel magic targeting "the closest object affected by sequester which I'm sensing but not seeing"?
Could you see it with see invisibility (or truesight)?
Can you dispel it if you pour some flour on it? This would arguably get rid of the invisible condition.
More for curiosity purposes, can you sense it and then dispel it with detect thoughts (PHB, 231) if it's a creature (maybe by sensing its dreams)?
Finally, would nondetection prevent all that (except for the flour)?
I found a tangent question, but didn't see enough evidence of its answer, so I'm asking in here in full.
Thank you all.