MEMO 2008 pojedinačno problem 1
Dodao/la:
arhiva28. travnja 2012. Let
be a sequence of integers with
For all quadruple
of indices such that
and
we have the inequality
Determine the least possible value of
.
%V0
Let $(a_n)^{\infty}_{n=1}$ be a sequence of integers with $a_{n} < a_{n+1}, \quad \forall n \geq 1.$ For all quadruple $(i,j,k,l)$ of indices such that $1 \leq i < j \leq k < l$ and $i + l = j + k$ we have the inequality $a_{i} + a_{l} > a_{j} + a_{k}.$ Determine the least possible value of $a_{2008}$.
Izvor: Srednjoeuropska matematička olimpijada 2008, pojedinačno natjecanje, problem 1