MathDB
Problems
Contests
National and Regional Contests
PEN Problems
PEN M Problems
11
11
Part of
PEN M Problems
Problems
(1)
M 11
Source:
5/25/2007
Let
a
1
=
11
11
a_{1}={11}^{11}
a
1
=
11
11
,
a
2
=
12
12
a_{2}={12}^{12}
a
2
=
12
12
,
a
3
=
13
13
a_{3}={13}^{13}
a
3
=
13
13
, and
a
n
=
∣
a
n
−
1
−
a
n
−
2
∣
+
∣
a
n
−
2
−
a
n
−
3
∣
,
n
≥
4.
a_{n}= \vert a_{n-1}-a_{n-2}\vert+\vert a_{n-2}-a_{n-3}\vert, n \ge 4.
a
n
=
∣
a
n
−
1
−
a
n
−
2
∣
+
∣
a
n
−
2
−
a
n
−
3
∣
,
n
≥
4.
Determine
a
14
14
a_{{14}^{14}}
a
14
14
.
Recursive Sequences