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1
2015 Algebra Tiebreaker #1
2015 Algebra Tiebreaker #1
Source:
July 1, 2022
2015
Algebra Tiebreaker
Problem Statement
Let
a
n
a_n
a
n
be a sequence defined as
a
1
=
1
a_1=1
a
1
=
1
,
a
2
=
2
a_2=2
a
2
=
2
, and
a
n
=
a
n
−
1
−
a
n
−
2
a_n=a_{n-1}-a_{n-2}
a
n
=
a
n
−
1
−
a
n
−
2
. Compute
a
2015
a_{2015}
a
2015
.
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