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by quakeguy 3376 days ago
Math tells me there must be 216, no? 3 quarks make a baryon, there are 6 types of quarks, so 6^3? Idk if up up up baryons are allowed though, or any other baryon made of 3 equal quarks.
3 comments

They are allowed (https://en.wikipedia.org/wiki/Delta_baryon). Also, you need to take into account the overall spin of the particle (may be either 1/2 or 3/2 depending on whether the quark spins all have the same direction or not) and the individual spins of the constituents. Check https://en.wikipedia.org/wiki/List_of_baryons for details.
You can also have excited particles that have the same quark content. They are called "resonances", are unstable and can decay. For example, the five particles discovered here are excitations of the particle containing two strange and one charm quark.
Pentaquarks are also theorized to exist: https://en.wikipedia.org/wiki/Pentaquark