2 , 3 , 6 , 15 , 45 , 156.5 , 630

As per the details in the question the series is in the form of
First term = 2
Second term = First term × 1.5
? Second term = 2 × 1.5 = 3 ;
Third term = Second term × 2
? Third term = 3 × 2 = 6 ;
Similarly , we can find all others terms also.
Fourth term = Third term × 2.5 = 6 × 2.5 = 15 ;
Fifth term = Fourth term × 3 = 15 × 3 = 45 ;
Sixth term = Fifth term × 3.5 = 45 × 3.5 =156.5; 156.5 is wrong. It should be 157.5 .
Seventh term = Sixth term × 4 =157.5 × 4 = 630
Hence, 156.5 is wrong. It should be 157.5.