Left most Digits of $5^n$
45240
Starting digits of $2^n$.
51826
Last digits number theory. $7^{9999}$?
150652
Number of 4-digit numerals with at most 2 different digits
56314
Which of the numbers $1, 2^{1/2}, 3^{1/3}, 4^{1/4}, 5^{1/5}, 6^{1/6} , 7^{1/7}$ is largest, and how to find out without calculator?
35169
Finding the limit of $\left(\frac{n}{n+1}\right)^n$
12760
The last 2 digits of $7^{7^{7^7}}$
49011
How to find last two digits of $2^{2016}$
32653
Smallest integer divisible by all up to $n$
149961
Two digit numbers
153302
$9$ divides $n-r(n)$ where $r(n)$ is $n$ with its digits reversed
5037
Find the last two digits of $3^{45}$
51299
How many digits is $99^{99}$ without a calculator?
144017
How to find the smallest $n$ such that $n^a\equiv 1 \pmod p$
142135
A number with 6 distinct digits which get multiplied by 5 if we move the last digit to front
45788
$n$-th digit in the sequence of natural numbers
67312
How to find the last digit of $3^{1000}$?
45456
Do the digits of $\pi$ contain every possible finite-length digit sequence?