This mathematician proved the product sum identity for a real-number analogue of the Riemann zeta fu
This mathematician proved the product sum identity for a real-number analogue of the Riemann zeta function and used its divergence at a value of one to show that there are infinitely many primes. As n goes to infinity, the difference between the nth harmonic number and the natural log of n goes to a constant of which he is the first namesake and that is symbolized gamma. For a polyhedron, the number of vertices minus number of edges plus number of faces is equal to his namesake characteristic, chi [rhymes with "eye"]. He inaugurated graph theory by solving the Seven Bridges of Königsberg [KER-nigs-bairg] problem. For 10 points, name this prolific mathematician who discovered a constant equal to about 2.718, the usual symbol for which is his last initial.
This mathematician proved the product sum identity for a real-number analogue of the Riemann zeta function and used its divergence at a value of one to show that there are infinitely many primes.
Leonhard Paul {Euler} [OIL-er]