Some Euler

William Dunham lectures at Cornell on two of Euler’s big theorems: the divergence of the sum of the reciprocals of the primes and the evaluation of the sum of the reciprocals of the squares
${1 \over 1} + {1 \over 4} + {1 \over 9} + {1 \over 16} + \cdots = {\pi^2 \over 6}$.

Dunham is the author of Euler: The Master of Us All, which focuses on selected results of Euler. If I recall correctly I first saw the evaluation of $\zeta(2)$ in his Journey through Genius.

This focuses on the math; there’s a full-length biography of Euler coming out, by Ronald Calinger. The publisher, Princeton, describes this as the “first full-scale biography of Leonhard Euler”, which is honestly a bit surprising.