Answer:
See We have to use rule 6n+1
where n represents position
that is, for 1st term n=1 , for 2nd term n=2 and so on
Now put n=1 in 6n+1
6(1) +1
= 6 +1
=7
Now put n=2
6(2) +1
= 12+1
=13
So, Sequence becomes
7,13,.....