Suppose in an infinitely long line, the hare is standing in position 0.
From that place, it can jump either in the +ve direction or in the -ve [but not both].
One condition is that, in i-th jump, it can move i step. Meaning -
0 1 [1st step >> so 0+1] 3 [2nd step >> so 1+2] 6 10
Given a position x, determine whether the hare will be in that position or not.
if x=15 then true if x=14 then false.