7, 26, 63, 124, 215, 342, (....)	Choose the correct choice from the following answers:
A) 481  B) 391  C) 511  D) 421  E) 452
Explanation :   The series is (2^3 - 1), (3^3 - 1), (4^3 - 1), (5^3 - 1), (6^3 - 1), (7^3 - 1), ...   Hence, next number is (8^3 - 1) = 511   Answer : Option 511
<result>C</result>
7, 26, 63, 124, 215, 342, (....)