Write definitions using elementhood tests for the following sets: {5, 10, 15, 20, 25, 30, .} { -4, -3, -2, -1, 0, 1, 2, 3} {2, 3, 5, 7, 11, 13, 17,...

1. Write definitions using elementhood tests for the following sets:

2. {5, 10, 15, 20, 25, 30, …}

1. { -4, -3, -2, -1, 0, 1, 2, 3}

1. {2, 3, 5, 7, 11, 13, 17, 19, 23, …} 

I know the first problem are multiples of 5 that goes to infinite. The second problem are the integers from negative 4 until positive 3 only. The third problem are natural numbers from 2 until infinite but I'm not sure if the braces notations I have are correct. Thank you for your help.