1* 1,2*2,3*3,4*4,5*5,6*6……

or

Last issue number +3, last issue number +5, last issue number +7, last issue number +9, last issue number+1 1 ...

(2) 1,4,9,( 15),( 18),(9)

The third term starts with the difference between the first two numbers multiplied by 3.

(3) 1,4,9,(22),(53),( 128)

The third item is equal to twice the sum of the previous item and the previous item.

(4) 1,4,9,(25),(67),( 183)

The third item starts with the sum of the first two items multiplied by 2 minus 1.