There are many infinite acyclic decimals, such as root number 2, root number 3, root number 5 and so on. But the two most famous infinite cyclic decimals are the base e of pi and natural logarithm. The base of natural logarithm e = 2.718281828459045.

E is a wonderful and interesting irrational number, which is taken from the English prefix of mathematician Euler.

Euler first discovered this number and called it a natural number. But the natural numbers mentioned here are different from common natural numbers: 1, 2, 3, 4. ...

To be exact, e should be called "the base of natural logarithm".

E and pi are considered as the two most important transcendental numbers in mathematics (numbers that do not satisfy any algebraic equation with integral coefficients are called transcendental numbers).

And there is a well-known relationship between e, π and imaginary number I: e (π) =- 1. The approximate value of e can be obtained by the following calculation formula:

e= 1+ 1/ 1！ + 1/2! + 1/3! +...+ 1/(n- 1)！ + 1/n！ , n is a positive integer.

n！ It means factorial, n! =n*(n- 1)*(n-2)*......*3*2* 1。

In addition, there is an uncommon infinite acyclic decimal: Euler constant γ = 0.5772156649015328 ... which is also a transcendental number.

E, pi, Euler constant γ, which is the most famous infinite acyclic decimal, namely irrational number.