| 1049 | Brave Balloonists | USU Local Contest. March 2000 | 5595 | 240 |
| 1086 | Cryptography | Spring School Contest 2001 | 11088 | 109 |
| 1091 | Tmutarakan Exams | USU Local Contest. March 2001 | 2288 | 501 |
| 1104 | Don’t Ask Woman about Her Age | Tetrahedron Team Online Contest May 2001 | 4738 | 93 |
| 1118 | Nontrivial Numbers | Autumn School Contest 2001 | 4333 | 103 |
| 1133 | Fibonacci Sequence | NEERC 2001 Central Subregional | 2441 | 182 |
| 1204 | Idempotents | USU Local Contest. March 2002 | 1966 | 227 |
| 1261 | Tips | Autumn School Contest 2003 | 1353 | 337 |
| 1286 | Starship Travel | USU Personal Contest 2004 | 670 | 680 |
| 1352 | Mersenne Primes | Spring School Contest 2005 | 3604 | 130 |
| 1355 | Bald Spot Revisited | Spring School Contest 2005 | 2143 | 217 |
| 1356 | Something Easier | Spring School Contest 2005 | 1326 | 350 |
| 1430 | Crime and Punishment | Timus Top Coders: First Challenge | 977 | 463 |
| 1456 | Jedi Riddle 2 | Timus Top Coders: Second Challenge | 582 | 758 |
| 1554 | Multiplicative Functions | Petrozavodsk Summer 2007. NSU Contest | 615 | 631 |
| 1560 | Elementary Symmetric Functions | Petrozavodsk Summer 2007. NSU Contest | 391 | 983 |
| 1698 | Square Country 5 | Petrozavodsk Winter 2009. USU Contest | 565 | 595 |
| 1748 | The Most Complex Number | Petrozavodsk Summer 2009. Ufa SATU Contest | 1226 | 253 |
| 1807 | Cartridges for Maxim | NEERC 2010 Eastern Subregional | 205 | 1343 |
| 2070 | Interesting Numbers | Ural Regional School Programming Contest 2015 | 735 | 198 |
| 2102 | Michael and Cryptography | Ural FU Junior Championship 2016 | 941 | 125 |
| 2117 | Polyphemus' triples | University academic school olympiad in informatics 2019 | 126 | 443 |
| 2124 | Algebra on Segment | Petrozavodsk Summer 2018. t.me/umnik_team Contest | 28 | 1525 |
| 2138 | The Good, the Bad and the Ugly | Ural School Programming Contest 2019 | 392 | 118 |
