ID NAME QUALITY USERS ACC % DIFFICULTY C I
30757 Ada and Carrot   5 104
17
34
32029 Ada and Connections   4 54
23
23
32840 Ada and Digits   14 143
21
18
32949 Ada and Digits 2   4 56
28
28
30739 Ada and Manure   17 245
11
22
30755 Ada and GCD   16 337
29
15
30691 Ada and Diary   1 45
1
1
30737 Ada and Homework   1 49
32683 Ada and Kohlrabi   5 49
30
13
32059 Ada and Taxes   15 82
22
22
5151 Alice’s Cube   7 484
26
23
10232 Distinct Primes   81 5366
9
8
4556 Think I will Buy Me a Football Team   28 2079
7
11
5451 Not So Flat After All   9 1094
11
10
13753 Amazing Prime Sequence   60 3127
11
12
30826 Bernoulli numbers   4 6
23
12
31066 Number Breaking   7 440
16
14
21357 Crucial Equation   75 5274
4
9
3505 Prime Number Theorem   19 1445
13
14
9032 Cube Free Numbers   61 3942
12
10
526 Divisors   35 1548
16
14
530 Divisors 2   9 794
15
17
22403 Divisors of factorial   66 1660
14
14
74 Divisor Summation   84 14527
7
10
23963 Easy Factorials   10 105
27
26
4141 Euler Totient Function   136 10012
8
11
22382 Euler Totient Function Depth   22 337
14
15
4942 Integer Factorization (15 digits)   44 2852
11
11
33046 Factorial Modulo Prime   3 15
45
39
25584 Factorial Modulo   25 370
10
15
25067 Fibonacci Polynomial   8 139
10
20
5970 Finding Primes   21 1261
17
15
6264 Rank of a Fraction   4 126
12
34
5978 Frequent Prime Ranges   8 635
14
12
3871 GCD Extreme   70 1807
19
26
26045 GCD OF MATRIX (hard)   2 32
50
17
12005 Grass Planting   7 298
34
17
18202 HUGE GCD   16 547
12
12
4164 A conjecture of Paul Erdős   19 1407
13
13
12241 Classification from Erdős and Selfridge   3 21
26
26
27195 Find The Number   7 194
20
17
6221 Increasing Powers of K   4 338
24
34
6256 Inversion Count   510 14189
16
18
40083 Just Primes   9 73
15
17
40084 Just Primes II   4 9
34
28
12183 Help the Commander in Chief   46 872
15
16
34812 Kth Power Summation   5 41
23
17
3442 The last digit   178 24034
9
8
5971 LCM Sum   73 2648
20
28
9385 Strictly not a Prime   8 353
17
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