ID NAME QUALITY USERS ACC % DIFFICULTY C I
30757 Ada and Carrot   3 27
6
28
32029 Ada and Connections   2 21
17
17
32840 Ada and Digits   8 40
19
17
32949 Ada and Digits 2   3 24
28
28
30739 Ada and Manure   9 106
8
24
30755 Ada and GCD   6 104
24
14
30691 Ada and Diary   26
30737 Ada and Homework   1 37
32683 Ada and Kohlrabi   2 22
34
9
32059 Ada and Taxes   6 27
20
20
5151 Alice’s Cube   7 439
26
23
10232 Distinct Primes   47 3756
10
9
4556 Think I will Buy Me a Football Team   20 1843
7
12
5451 Not So Flat After All   7 1033
12
8
13753 Amazing Prime Sequence   35 2437
10
12
30826 Bernoulli numbers   2 4
17
17
31066 Number Breaking   3 129
11
11
21357 Crucial Equation   39 2641
3
10
3505 Prime Number Theorem   14 1171
12
14
9032 Cube Free Numbers   33 3023
13
12
526 Divisors   21 1150
17
13
530 Divisors 2   5 679
15
17
22403 Divisors of factorial   47 1094
15
14
74 Divisor Summation   53 11611
7
10
23963 Easy Factorials   10 72
28
28
4141 Euler Totient Function   80 6642
8
12
22382 Euler Totient Function Depth   16 228
14
14
4942 Integer Factorization (15 digits)   22 1909
13
12
33046 Factorial Modulo Prime   2 3
42
34
25584 Factorial Modulo   18 293
9
13
25067 Fibonacci Polynomial   5 90
23
23
5970 Finding Primes   15 902
18
16
6264 Rank of a Fraction   3 109
9
34
5978 Frequent Prime Ranges   4 567
13
10
3871 GCD Extreme   37 907
20
26
26045 GCD OF MATRIX (hard)   1 6
12005 Grass Planting   3 128
38
17
18202 HUGE GCD   8 419
8
14
4164 A conjecture of Paul Erdős   3 553
9
13
12241 Classification from Erdős and Selfridge   3 19
26
26
27195 Find The Number   4 142
14
11
6221 Increasing Powers of K   2 303
26
34
6256 Inversion Count   296 9664
16
18
12183 Help the Commander in Chief   22 402
14
16
3442 The last digit   92 16298
9
9
5971 LCM Sum   36 1444
20
30
9385 Strictly not a Prime   6 294
20
15
6450 PP numbers   3 743
17
17
3932 Point Connection Game in a Circle   1 628
17
26
34567 Least prime divisor   1 12

#number-theory

The problem involves number theory, a branch of pure mathematics

https://en.wikipedia.org/wiki/Number_theory http://mathworld.wolfram.com/NumberTheory.html http://www.math.brown.edu/~jhs/frintch1ch6.pdf http://www.britannica.com/topic/number-theory