Arrange - 3, - 1, 1, 3, 5, 7, 9... According to the rule, then the nth number is? (n is an integer)

Arrange - 3, - 1, 1, 3, 5, 7, 9... According to the rule, then the nth number is? (n is an integer)

It is obvious that the difference is 2, so d = 2, according to the formula an = a1 + (n-1) d
A1= -3,
So an = 2n-5