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ISI B.Stat Entrance Exam
2006 ISI B.Stat Entrance Exam
7
a combinatorial inequality
a combinatorial inequality
Source: ISI Bstat Entrance, 2006
March 1, 2012
inequalities
induction
algebra unsolved
algebra
Problem Statement
for any positive integer
n
n
n
greater than
1
1
1
, show that
2
n
<
(
2
n
n
)
<
2
n
∏
i
=
0
n
−
1
(
1
−
i
n
)
2^n<\binom{2n}{n}<\frac{2^n}{\prod\limits_{i=0}^{n-1} \left(1-\frac{i}{n}\right)}
2
n
<
(
n
2
n
)
<
i
=
0
∏
n
−
1
(
1
−
n
i
)
2
n
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