For 10 points, name this mathematician whose namesake number is approximately 2.718 and denoted with a lowercase e.
With Maclaurin, this man lends his name to a formula for evaluating finite sums and infinite series with integrals. His namesake formula relates trigonometric functions and the complex exponential function. He names a constant symbolized lowercase gamma with Mascheroni, considered the father of (*) graph theory for his solution of the Seven Bridges of Königsberg Problem. For 10 points, name this mathematician whose namesake number is approximately 2.718 and denoted with a lowercase e.
With Maclaurin, this man lends his name to a formula for evaluating finite sums and infinite series with integrals.
Leonhard {Euler}