Cleo

Vladimir Reshetnikov (born 1979) is an Uzbekistani-American software developer and mathematician who became known for providing precise answers to complex mathematical integration problems without showing any intermediate steps under the pseudonym Cleo. Due to the extraordinary accuracy and speed of the provided solutions, it was debated online whether Cleo was an individual genius or a collective pseudonym system.

During the poster's active period, Cleo posted 39 answers to advanced mathematical questions, primarily focusing on complex integration problems that had stumped other users. Cleo's answers were characterized by being consistently correct while providing no explanation of methodology, often appearing within hours of the original posts. The account claimed to be limited in interaction due to an unspecified medical condition.

The mystery surrounding Cleo's identity and mathematical abilities generated interest within the mathematical community, and some users attempted to analyze solution patterns and writing style for clues. Some compared Cleo to historical mathematical figures like Srinivasa Ramanujan, who was known for providing solutions without conventional proofs. In January 2025, Cleo was revealed to be Vladimir Reshetnikov.

History Background On to Cleo's mathematics Stack Exchange (also known as Math.SE) profile, they presented themself as a female mathematician with an undisclosed medical condition that limited their ability to engage in extended discussions or provide detailed explanations. Cleo posted 39 answers to problems that primarily involved complicated mathematical integration. Their first notable contribution occurred on 11 November 2013 when they solved a particularly difficult integral that had stumped other users:

Ron Gordon's solution to the integral involved a contour integral over a keyhole contour and extensive symmetry analysis. The solution was simply stated by Cleo four and a half hours later as , where is the golden ratio. The answer included only a hyperlink defining the golden ratio with no supporting work. Stephen Hawking,

Reshetnikov studied theoretical physics at the National University of Uzbekistan in the late 1990s. He worked as a software developer in Tashkent before moving to the United States, where he was employed by Microsoft for several years. He is an active contributor to the Mathematics Stack Exchange. On 8 February 2025, Reshetnikov posted a Base64-encoded message on his Stack Exchange profile that, when decoded, read "Creator of Cleo". Similar encoded messages appeared on related accounts, including those of "Laila Podlesny" and "Oksana Gimmel", confirming these were also alternate accounts created by Reshetnikov. Reshetnikov explained that he created the Cleo persona to generate interest in mathematical problems that received little attention on the forum. According to him, the mysterious nature of the account and its terse solutions were intended to encourage other users to develop their own problem-solving approaches.