Question 1
(BUL 1) Prove that all numbers in the sequence
$$\frac{107811}{3},\quad\frac{110778111}{3},\quad\frac{111077781111}{3},\quad\ldots$$
are perfect cubes.
$$\frac{107811}{3},\quad\frac{110778111}{3},\quad\frac{111077781111}{3},\quad\ldots$$
are perfect cubes.