*The Reader’s challenge :*

**What will be the 99**^{th} term of the following series, which follows a certain rule.

1, 2, 3, 4, 10, 5, 6, 7, 8, 26, 9, 10, 11, 12, 42………

*Expert’s challenge: *

*Find out a general formula for finding the n*^{th} term of the given series.