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Putnam
1974 Putnam
A4
Putnam 1974 A4
Putnam 1974 A4
Source: Putnam 1974
May 28, 2022
Putnam
expected value
coin tosses
Problem Statement
An unbiased coin is tossed
n
n
n
times. What is the expected value of
∣
H
−
T
∣
|H-T|
∣
H
−
T
∣
, where
H
H
H
is the number of heads and
T
T
T
is the number of tails?
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