MathDB
Problems
Contests
National and Regional Contests
India Contests
Postal Coaching
2010 Postal Coaching
7
Existence of a Function
Existence of a Function
Source:
December 9, 2010
function
algebra unsolved
algebra
Problem Statement
Does there exist a function
f
:
N
→
N
f : \mathbb{N} \rightarrow \mathbb{N}
f
:
N
→
N
such that for every
n
≥
2
n \ge 2
n
≥
2
,
f
(
f
(
n
−
1
)
)
=
f
(
n
+
1
)
−
f
(
n
)
?
f (f (n - 1)) = f (n + 1) - f (n)?
f
(
f
(
n
−
1
))
=
f
(
n
+
1
)
−
f
(
n
)?
Back to Problems
View on AoPS