The missing term of the sequence7, 26, 63, 124, 215, 342, ____, 728 is
391
421
481
D.
The pattern of the number series is23 - 1 = 733 - 1 = 2643 - 1 = 6353 - 1 = 12463 - 1 = 21573 - 1 = 34283 - 1 =