I was doing the following question:
Find a simpler way to specify the set $A=\big\{ X: X\in \Bbb N \cap \{-5,3,7,11\} \cup \{-5, -3, 13\} \big\}$
Am I right to suggest a simpler way of specifying the following sets is
$A=\big\{X:X\in \Bbb N \cup \{-5,-3\} \big\} ~?$
Thank you in advance!