I have a set C which is defined as: $$ C= \{ (x|x\in \mathbb Z^+) \land ( x \pmod 3 < 2) \} $$
To find such an x, we have: $x = 3n + 1$
But what am I limited to in this case? if $ n=1 $ then $x=4$. But am I limited to positive integers less than two? Meaning: $C=\{4\}$
I'm a little confused here.