ID NAME QUALITY USERS ACC % DIFFICULTY C I
42 Adding Reversed Numbers   48 39841
6
4
25942 Ball sum   27 962
11
11
30826 Bernoulli numbers   2 3
17
17
24998 PLAYING WITH BITS   24 469
14
14
17921 XOR   -10 2951
1
1
18294 Problem1   44
26314 Corn Headache   5 206
8
6
27269 Cube Numbers   22 416
10
11
22403 Divisors of factorial   40 929
15
14
27299 Find Log   2 50
1
1
25311 Candies   3 715
6
8
32445 COUNT JUMPS   3 50
6
1
25583 Easy Odd Sum   2 801
3
3
31 Fast Multiplication   28 3211
13
13
16272 Nanoworld   8
25008 New Currency Shopping   1 3
34
17
15708 Divisibility   6 3175
6
5
17104 Fun with Sequences (Act 3)   1 678
1
1
17126 Fun with Sequences (Act 4)   2 371
1
1
17481 Fun with Sequences (Act 5)   291
1
1
18011 Fun with Sequences (Act 6)   376
1
1
18012 Fun with Sequences (Act 7)   318
1
1
176 Sum of one-sequence   4 604
1
23
22455 SUM OF PRODUCT   27 734
20
20
235 Very Fast Multiplication   7 564
30
17

#simple-math

The problem involves but simple mathematical concepts like arithmetic operations

http://www.basic-mathematics.com