[25P] The Number Triangle

[Atul Nischal]

Consider numbers 91 to 100. 

1. Which of these numbers can be written in the form ab + a + b + 1 in the greatest number of ways, given that a and b are positive integers and a ≤ b?
2. Which integer, if any, cannot be written in the form ab + a + b + 1, given that a and b are positive integers and a ≤ b?
   

Hint: 95 = 4 × 18 + 4 + 18 + 1. [For, a = 4 and b = 18, we have written 95 in the form ab + a + b + 1]