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1979 IMO Longlists
2
2
Part of
1979 IMO Longlists
Problems
(1)
Calculate number of 3-element subsets with the property
Source: IMO LongList 1979 - P2
5/29/2011
For a finite set
E
E
E
of cardinality
n
≥
3
n \geq 3
n
≥
3
, let
f
(
n
)
f(n)
f
(
n
)
denote the maximum number of
3
3
3
-element subsets of
E
E
E
, any two of them having exactly one common element. Calculate
f
(
n
)
f(n)
f
(
n
)
.
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