2 , 3 , 5 , 8 , 14 , 23 , 41, 69

The series is an alternate series, having
Odd position series :-
First term = 2
Third term = ( First term × 3 ) - 1
⇒ Third term = ( 2 × 3 ) - 1 = 5 ;
Fifth term = ( Third term × 3 ) - 1
⇒ Fifth term = ( 5 × 3 ) - 1 = 14 ;
Seventh term = ( Fifth term × 3 ) - 1
⇒Seventh term = ( 14 × 3 ) - 1 = 41 ;
Even position series :-
Second term = 3
Fourth term = ( Second term × 3 ) - 1
⇒ Fourth term = ( 3 × 3 ) - 1 = 8 ;
Sixth term = ( Fourth term × 3 ) - 1
⇒ Sixth term = ( 8 × 3 ) - 1 = 23 ;
Eighth term = ( Sixth term × 3 ) - 1
⇒ Eighth term = ( 23 × 3 ) - 1 = 69; 69 is wrong. It should be 68.