As a mathematical constant, e is the base of natural logarithmic function. It is sometimes called Euler number, named after the Swiss mathematician Euler. There is also a relatively rare name, Napier constant, to commemorate the Scottish mathematician John? Napier introduced logarithm, which is one of the most important constants in mathematics, just like pi and imaginary units I and E. Its value is about (decimal point 100): e ≈ 2.7182818284 59045 23536 02874 71352 66249 77572 47093 69995 95749 666. 4759 4571382178 52516 64274 first mentioned the constant e, which is a table in the appendix of John Napier's logarithmic works published in 16 18. However, it does not record this constant, only a table calculated from it. It is generally believed that it was made in William Oughtred. It was Jacob Bernoulli who first thought that E was a constant. The first known use of the constant e is the communication between Leibniz and Huygens at 1690 and 169 1, which is represented by b.56438+08. Euler's mechanics used e for the first time in the publication 1736. Although some researchers later used the letter C, E was more commonly used and eventually became the standard.