| 1049 | Brave Balloonists | USU Local Contest. March 2000 | 5921 | 244 |
| 1086 | Cryptography | Spring School Contest 2001 | 12301 | 106 |
| 1091 | Tmutarakan Exams | USU Local Contest. March 2001 | 2356 | 522 |
| 1104 | Don’t Ask Woman about Her Age | Tetrahedron Team Online Contest May 2001 | 5063 | 94 |
| 1118 | Nontrivial Numbers | Autumn School Contest 2001 | 4647 | 103 |
| 1133 | Fibonacci Sequence | NEERC 2001 Central Subregional | 2159 | 221 |
| 1204 | Idempotents | USU Local Contest. March 2002 | 2115 | 226 |
| 1261 | Tips | Autumn School Contest 2003 | 1465 | 333 |
| 1286 | Starship Travel | USU Personal Contest 2004 | 724 | 672 |
| 1352 | Mersenne Primes | Spring School Contest 2005 | 3842 | 130 |
| 1355 | Bald Spot Revisited | Spring School Contest 2005 | 2359 | 211 |
| 1356 | Something Easier | Spring School Contest 2005 | 1690 | 294 |
| 1430 | Crime and Punishment | Timus Top Coders: First Challenge | 1046 | 462 |
| 1456 | Jedi Riddle 2 | Timus Top Coders: Second Challenge | 636 | 744 |
| 1554 | Multiplicative Functions | Petrozavodsk Summer 2007. NSU Contest | 666 | 635 |
| 1560 | Elementary Symmetric Functions | Petrozavodsk Summer 2007. NSU Contest | 458 | 917 |
| 1698 | Square Country 5 | Petrozavodsk Winter 2009. USU Contest | 602 | 621 |
| 1748 | The Most Complex Number | Petrozavodsk Summer 2009. Ufa SATU Contest | 1359 | 258 |
| 1807 | Cartridges for Maxim | NEERC 2010 Eastern Subregional | 227 | 1393 |
| 2070 | Interesting Numbers | Ural Regional School Programming Contest 2015 | 930 | 209 |
| 2102 | Michael and Cryptography | Ural FU Junior Championship 2016 | 1297 | 130 |
| 2117 | Polyphemus' triples | University academic school olympiad in informatics 2019 | 209 | 524 |
| 2124 | Algebra on Segment | Petrozavodsk Summer 2018. t.me/umnik_team Contest | 91 | 1114 |
| 2138 | The Good, the Bad and the Ugly | Ural School Programming Contest 2019 | 1018 | 100 |
