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From 0-99.

The only one cannot pick is 42 which is retired across baseball for Jackie Robinson and some teams have retired numbers for some of their great players.

For the Mets 17, 41, 31, 37, and some others are retired.

I see... but do numbers have any relation with the position they play

Not exactly although there are some characteristics. You rarely see a pitcher with a single digit number. Also relief pichers tend to have some higher numbers...in the 50s and 60s.