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KoMaL A Problems
KoMaL A Problems 2020/2021
A. 785
A. 785
Part of
KoMaL A Problems 2020/2021
Problems
(1)
Kömal probability
Source: Kömal A.785
4/2/2021
Let
k
≥
t
≥
2
k\ge t\ge 2
k
≥
t
≥
2
positive integers. For integers
n
≥
k
n\ge k
n
≥
k
let
p
n
p_n
p
n
be the probability that if we choose
k
k
k
from the first
n
n
n
positive integers randomly, any
t
t
t
of the
k
k
k
chosen integers have greatest common divisor
1
1
1
. Let qn be the probability that if we choose
k
−
t
+
1
k-t+1
k
−
t
+
1
from the first
n
n
n
positive integers the product is not divisible by a perfect
t
t
h
t^{th}
t
t
h
power that is greater then
1
1
1
.Prove that sequences
p
n
p_n
p
n
and
q
n
q_n
q
n
converge to the same value.
probability