Find the odd man out of the number series? 18, 37, 76, 155, 314, 635

Given Number series is 18     37     76     155     314     635

follows a pattern that, 

18

18 x 2 +1 = 37

37 x 2 +2 = 76

76 x 2 +3 = 155

155 x 2 +4 = 314

314 x 2 +5 = 633 not 635

Hence, the odd man is 635.