ID NAME QUALITY USERS ACC % DIFFICULTY C I
30757 Ada and Carrot   5 88
17
34
32029 Ada and Connections   4 48
23
23
32840 Ada and Digits   14 130
21
18
32949 Ada and Digits 2   4 47
28
28
30739 Ada and Manure   15 219
11
22
30755 Ada and GCD   15 277
29
16
30691 Ada and Diary   1 38
1
1
30737 Ada and Homework   1 49
32683 Ada and Kohlrabi   5 46
30
13
32059 Ada and Taxes   13 69
23
23
5151 Alice’s Cube   7 475
26
23
10232 Distinct Primes   74 4956
9
8
4556 Think I will Buy Me a Football Team   28 2043
7
11
5451 Not So Flat After All   9 1081
11
10
13753 Amazing Prime Sequence   51 2968
10
12
30826 Bernoulli numbers   4 6
23
12
31066 Number Breaking   7 314
16
14
21357 Crucial Equation   70 4453
4
9
3505 Prime Number Theorem   17 1360
12
14
9032 Cube Free Numbers   57 3695
12
11
526 Divisors   34 1470
16
14
530 Divisors 2   8 760
15
17
22403 Divisors of factorial   60 1488
14
14
74 Divisor Summation   74 13780
7
10
23963 Easy Factorials   10 102
27
26
4141 Euler Totient Function   125 9094
8
11
22382 Euler Totient Function Depth   20 315
13
14
4942 Integer Factorization (15 digits)   36 2605
11
12
33046 Factorial Modulo Prime   2 12
42
34
25584 Factorial Modulo   23 361
10
15
25067 Fibonacci Polynomial   8 134
10
20
5970 Finding Primes   20 1148
16
14
6264 Rank of a Fraction   4 124
12
34
5978 Frequent Prime Ranges   7 622
14
12
3871 GCD Extreme   63 1463
19
26
26045 GCD OF MATRIX (hard)   2 29
50
17
12005 Grass Planting   6 229
37
17
18202 HUGE GCD   14 521
11
12
4164 A conjecture of Paul Erdős   11 1050
12
10
12241 Classification from Erdős and Selfridge   3 21
26
26
27195 Find The Number   7 190
20
17
6221 Increasing Powers of K   4 329
24
34
6256 Inversion Count   480 12752
16
18
12183 Help the Commander in Chief   44 813
15
16
34812 Kth Power Summation   4 42
20
17
3442 The last digit   171 21074
9
8
5971 LCM Sum   64 2238
19
28
9385 Strictly not a Prime   8 340
17
12
6450 PP numbers   8 836
11
4
3932 Point Connection Game in a Circle   2 689
12
17

#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