MathDB
Problems
Contests
International Contests
Lusophon Mathematical Olympiad
2015 Lusophon Mathematical Olympiad
6
NT sequence
NT sequence
Source: Cplp Problem 6
July 15, 2017
number theory
Sequences
Divisibility
Problem Statement
Let
(
a
n
)
(a_n)
(
a
n
)
be defined by:
a
1
=
2
,
a
n
+
1
=
a
n
3
−
a
n
+
1
a_1 = 2, \qquad a_{n+1} = a_n^3 - a_n + 1
a
1
=
2
,
a
n
+
1
=
a
n
3
−
a
n
+
1
Consider positive integers
n
,
p
n,p
n
,
p
, where
p
p
p
is an odd prime. Prove that if
p
∣
a
n
p | a_n
p
∣
a
n
, then
p
>
n
p > n
p
>
n
.
Back to Problems
View on AoPS