| 1049 | Brave Balloonists | USU Local Contest. March 2000 | 5794 | 241 |
| 1086 | Cryptography | Spring School Contest 2001 | 11679 | 108 |
| 1091 | Tmutarakan Exams | USU Local Contest. March 2001 | 2308 | 515 |
| 1104 | Don’t Ask Woman about Her Age | Tetrahedron Team Online Contest May 2001 | 4927 | 93 |
| 1118 | Nontrivial Numbers | Autumn School Contest 2001 | 4525 | 102 |
| 1133 | Fibonacci Sequence | NEERC 2001 Central Subregional | 2104 | 219 |
| 1204 | Idempotents | USU Local Contest. March 2002 | 2060 | 225 |
| 1261 | Tips | Autumn School Contest 2003 | 1423 | 332 |
| 1286 | Starship Travel | USU Personal Contest 2004 | 708 | 666 |
| 1352 | Mersenne Primes | Spring School Contest 2005 | 3753 | 129 |
| 1355 | Bald Spot Revisited | Spring School Contest 2005 | 2241 | 215 |
| 1356 | Something Easier | Spring School Contest 2005 | 1480 | 325 |
| 1430 | Crime and Punishment | Timus Top Coders: First Challenge | 1019 | 460 |
| 1456 | Jedi Riddle 2 | Timus Top Coders: Second Challenge | 609 | 752 |
| 1554 | Multiplicative Functions | Petrozavodsk Summer 2007. NSU Contest | 638 | 636 |
| 1560 | Elementary Symmetric Functions | Petrozavodsk Summer 2007. NSU Contest | 416 | 968 |
| 1698 | Square Country 5 | Petrozavodsk Winter 2009. USU Contest | 585 | 608 |
| 1748 | The Most Complex Number | Petrozavodsk Summer 2009. Ufa SATU Contest | 1301 | 255 |
| 1807 | Cartridges for Maxim | NEERC 2010 Eastern Subregional | 218 | 1360 |
| 2070 | Interesting Numbers | Ural Regional School Programming Contest 2015 | 838 | 204 |
| 2102 | Michael and Cryptography | Ural FU Junior Championship 2016 | 1108 | 130 |
| 2117 | Polyphemus' triples | University academic school olympiad in informatics 2019 | 165 | 505 |
| 2124 | Algebra on Segment | Petrozavodsk Summer 2018. t.me/umnik_team Contest | 55 | 1325 |
| 2138 | The Good, the Bad and the Ugly | Ural School Programming Contest 2019 | 735 | 102 |
