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23
2016 Guts #23
2016 Guts #23
Source:
December 24, 2016
Problem Statement
Let
t
=
2016
t = 2016
t
=
2016
and
p
=
ln
2
p = \ln 2
p
=
ln
2
. Evaluate in closed form the sum
∑
k
=
1
∞
(
1
−
∑
n
=
0
k
−
1
e
−
t
t
n
n
!
)
(
1
−
p
)
k
−
1
p
.
\sum_{k=1}^{\infty} \left( 1-\sum_{n=0}^{k-1}\frac{e^{-t}t^{n}}{n!} \right) \left(1-p\right)^{k-1}p.
k
=
1
∑
∞
(
1
−
n
=
0
∑
k
−
1
n
!
e
−
t
t
n
)
(
1
−
p
)
k
−
1
p
.
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