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Blast into Math! Analatic nummer theora: ants, ghosts and giants
Nonsense! The inequalities mean that 1 > 1 which is false. So, by contradiction we have proven that
there is only one real number y such that
y
e = x,
and
log(x)= y.
∞
The Prime Number Theorem uses the natural logarithm to describe how quickly the sequence {P n } n=1
marches towards infinity.
Theorem 7.5.3 (Prime Number Theorem). For n ∈ N , define
P n =the number of primes less than or equalto n.
Then, let
P n
x n = .
n/ log(n)
∞ converges to 1,
The sequence {x n } n=1
P n
lim =1.
n→∞ n/ log(n)
What does it mean? For any ghost number > 0, there exists a giant number N ∈ N such that
∀n> N, |x n − 1| <.
So, for example, there exists N ∈ N such that
P n
− 1 < 0.1, ∀n> N.
n/ log(n)
This means that
P n
0.9 < < 1.1, ∀n> N,
n/ log(n)
which we can re-arrange to
n n
0.9 <P n < 1.1 , ∀ n> N.
log(n) log(n)
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