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Romania Team Selection Test
1992 Romania Team Selection Test
1
increasing f : N \to N , t f(f(n)) = 3n , f(1992) =?
increasing f : N \to N , t f(f(n)) = 3n , f(1992) =?
Source: Romania BMO TST 1992 p1
February 19, 2020
functional
function
algebra
Problem Statement
Suppose that
f
:
N
ā
N
f : N \to N
f
:
N
ā
N
is an increasing function such that
f
(
f
(
n
)
)
=
3
n
f(f(n)) = 3n
f
(
f
(
n
))
=
3
n
for all
n
n
n
. Find
f
(
1992
)
f(1992)
f
(
1992
)
.
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