Find the invalid no.from the following series 3, 7, 15, 27, 63, 127, 255
Choose the correct answer:
A) 3  B) 7  C) 27  D) 63  E) 127
Go on multiplying the number by 2 and adding 1 to it to get the next number.So, 27 is wrong.   27
<result>C</result>
Find the invalid no.from the following series 3, 7, 15, 27, 63, 127, 255