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Rioplatense Mathematical Olympiad, Level 3
2001 Rioplatense Mathematical Olympiad, Level 3
3
3
Part of
2001 Rioplatense Mathematical Olympiad, Level 3
Problems
(1)
another sequence with floor function, prove S_{2001}=2S_{2000}+1
Source: Rioplatense Olympiad 2001 level 3 P3
9/6/2018
For every integer
n
>
1
n > 1
n
>
1
, the sequence
(
S
n
)
\left( {{S}_{n}} \right)
(
S
n
)
is defined by
S
n
=
⌊
2
n
2
+
2
+
.
.
.
+
2
⏟
n
r
a
d
i
c
a
l
s
⌋
{{S}_{n}}=\left\lfloor {{2}^{n}}\underbrace{\sqrt{2+\sqrt{2+...+\sqrt{2}}}}_{n\ radicals} \right\rfloor
S
n
=
2
n
n
r
a
d
i
c
a
l
s
2
+
2
+
...
+
2
where
⌊
x
⌋
\left\lfloor x \right\rfloor
⌊
x
⌋
denotes the floor function of
x
x
x
. Prove that
S
2001
=
2
S
2000
+
1
{{S}_{2001}}=2\,{{S}_{2000}}+1
S
2001
=
2
S
2000
+
1
. .
algebra
floor function
function
Sequence
radical