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9
2004 Calculus #9
2004 Calculus #9
Source:
November 29, 2011
calculus
limit
ratio
algebra
polynomial
logarithms
absolute value
Problem Statement
Find the positive constant
c
0
c_0
c
0
such that the series
∑
n
=
0
∞
n
!
(
c
n
)
n
\displaystyle\sum_{n = 0}^{\infty} \dfrac {n!}{(cn)^n}
n
=
0
∑
∞
(
c
n
)
n
n
!
converges for
c
>
c
0
c>c_0
c
>
c
0
and diverges for
0
<
c
<
c
0
0<c<c_0
0
<
c
<
c
0
.
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