MathDB
Problems
Contests
National and Regional Contests
USA Contests
USA - College-Hosted Events
BMT Problems
2012 BMT Spring
5
Spring Round (2012) #5
Spring Round (2012) #5
Source:
December 3, 2012
Problem Statement
Let
a
↑
↑
b
=
a
a
a
…
a
a
{ a\uparrow\uparrow b = {{{{{a^{a}}^a}^{\dots}}}^{a}}^{a}}
a
↑↑
b
=
a
a
a
…
a
a
, where there are
b
b
b
a's in total. That is
a
↑
↑
b
a\uparrow\uparrow b
a
↑↑
b
is given by the recurrence
a
↑
↑
b
=
{
a
b
=
1
a
a
↑
↑
(
b
−
1
)
b
≥
2
a\uparrow\uparrow b = \begin{cases} a & b=1\\ a^{a\uparrow\uparrow (b-1)} & b\ge2\end{cases}
a
↑↑
b
=
{
a
a
a
↑↑
(
b
−
1
)
b
=
1
b
≥
2
What is the remainder of
3
↑
↑
(
3
↑
↑
(
3
↑
↑
3
)
)
3\uparrow\uparrow( 3\uparrow\uparrow ( 3\uparrow\uparrow 3))
3
↑↑
(
3
↑↑
(
3
↑↑
3
))
when divided by
60
60
60
?
Back to Problems
View on AoPS