| 1049 | Brave Balloonists | USU Local Contest. March 2000 | 5856 | 241 |
| 1086 | Cryptography | Spring School Contest 2001 | 11926 | 107 |
| 1091 | Tmutarakan Exams | USU Local Contest. March 2001 | 2338 | 516 |
| 1104 | Don’t Ask Woman about Her Age | Tetrahedron Team Online Contest May 2001 | 4986 | 93 |
| 1118 | Nontrivial Numbers | Autumn School Contest 2001 | 4571 | 102 |
| 1133 | Fibonacci Sequence | NEERC 2001 Central Subregional | 2126 | 220 |
| 1204 | Idempotents | USU Local Contest. March 2002 | 2084 | 225 |
| 1261 | Tips | Autumn School Contest 2003 | 1443 | 332 |
| 1286 | Starship Travel | USU Personal Contest 2004 | 715 | 668 |
| 1352 | Mersenne Primes | Spring School Contest 2005 | 3783 | 129 |
| 1355 | Bald Spot Revisited | Spring School Contest 2005 | 2273 | 215 |
| 1356 | Something Easier | Spring School Contest 2005 | 1526 | 319 |
| 1430 | Crime and Punishment | Timus Top Coders: First Challenge | 1033 | 459 |
| 1456 | Jedi Riddle 2 | Timus Top Coders: Second Challenge | 618 | 751 |
| 1554 | Multiplicative Functions | Petrozavodsk Summer 2007. NSU Contest | 654 | 631 |
| 1560 | Elementary Symmetric Functions | Petrozavodsk Summer 2007. NSU Contest | 449 | 913 |
| 1698 | Square Country 5 | Petrozavodsk Winter 2009. USU Contest | 592 | 613 |
| 1748 | The Most Complex Number | Petrozavodsk Summer 2009. Ufa SATU Contest | 1326 | 256 |
| 1807 | Cartridges for Maxim | NEERC 2010 Eastern Subregional | 221 | 1378 |
| 2070 | Interesting Numbers | Ural Regional School Programming Contest 2015 | 864 | 209 |
| 2102 | Michael and Cryptography | Ural FU Junior Championship 2016 | 1209 | 128 |
| 2117 | Polyphemus' triples | University academic school olympiad in informatics 2019 | 178 | 528 |
| 2124 | Algebra on Segment | Petrozavodsk Summer 2018. t.me/umnik_team Contest | 76 | 1128 |
| 2138 | The Good, the Bad and the Ugly | Ural School Programming Contest 2019 | 851 | 101 |
