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In 1733, a significant career advancement came when Euler succeeded Daniel Bernoulli as the senior chair of mathematics at the Academy. It was during these formative years that Euler not only cultivated personal relationships—including his marriage to Katharina Gsell—but also solidified his status as a leading mathematician of his time. Euler's early work laid the foundation for future discoveries, including the solution to the Basel Problem, revealing surprising links between number theory and the geometric constant π (pi).