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Cono Sur Olympiad
1998 Cono Sur Olympiad
1
1
Part of
1998 Cono Sur Olympiad
Problems
(1)
How many ways???
Source: Cono sur Olympiad 1997 P1
11/14/2017
We have
98
98
98
cards, in each one we will write one of the numbers:
1
,
2
,
3
,
4
,
.
.
.
.
,
97
,
98
1, 2, 3, 4,...., 97, 98
1
,
2
,
3
,
4
,
....
,
97
,
98
. We can order the
98
98
98
cards, in a sequence such that two consecutive numbers
X
X
X
and
Y
Y
Y
and the number
X
ā
Y
X - Y
X
ā
Y
is greater than
48
48
48
, determine how and how many ways we can make this sequence!!
combinatorics
algebra