Definition of the number e - gilt lead lithograph on white marble The definition as the limit of one of the five most important numbers in Mathematics, and the gateway to Calculus, the "higher mathematics." This is the classical definition, which is how the number was discovered: the limit of the total capital obtained from an investment of 1 monetary unit at 100% interest renewed over infinite periods; although it can also be defined as an infinite sum of inverses of factorial numbers. It is omnipresent in mathematics, from natural logarithms to differential equations, through statistics (normal probability distribution) and complex numbers (De Moivre's formula).

The work is handcrafted on a slab of excellent white marble, with each section of lead painstakingly measured, cut, and attached over several days of artisanal work. I can optionally protect the work with a layer of clear epoxy resin, according to the client's taste.