2

2

2

2

2

2

2

2

2

2

They begin by the digits 1,2,3,4,5,6 or 8.

Smallest power of 2 beginning by a 7 ? a 9 ?

Solution

It can be shown that for any number n, there is a power of 2
beginning by the digits of n.

Smallest power of 2 beginning by 100 ? by 1000 ?
by 123456789 ?

Solution