Show all final 2-digit numbers of the decimal expansions of squares are to be found among those of $0^2, 1^2,...25^2$
56985
Show that every positive integer has a unique representation in the form $50k+l$...?
56327
How to find the square root of a permutation
49967
Find the last two digits of $ 7^{81} ?$
20486
Numbers representable as $x^2 + 2y^2$
157186
Finding integers satisfying $m^2 - n^2 = 1111$
18932
Squares in arithmetic progression
108238
Find the smallest integer $n$ greater than $1$ such that the last $3$ digits of $n^2$ are the same as the last $3$ digits of $n$.
149961
Two digit numbers
134377
The minimum number of digits after the floating-point, which uniquely identify every irrational square root
20135
Measure of  reals in $[0,1]$ which don't have $4$ in decimal expansion
96204
Irrational number $\sqrt2$ proof
11506
Alternative proof that $(a^2+b^2)/(ab+1)$ is a square when it's an integer
98440
Show that any non-negative rational integer may be written as the sum of two squares if it is of the form....
45240
Starting digits of $2^n$.
127446
How do we find a fraction with whose decimal expansion has a given repeating pattern?
14073
Is there a way to determine how many digits a power of 2 will contain?
10920
$\delta_2(n)$ the sum of the squares of the positive divisors of $n$.