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2015 Azerbaijan JBMO TST
2015 Azerbaijan JBMO TST
Source: 2015 Azerbaijan JBMO TST
May 2, 2015
combinatorics
Problem Statement
A
=
1
⋅
4
⋅
7
⋯
2014
A=1\cdot4\cdot7\cdots2014
A
=
1
⋅
4
⋅
7
⋯
2014
.Find the last non-zero digit of
A
A
A
if it is known that
A
≡
1
m
o
d
3
A\equiv 1\mod3
A
≡
1
mod
3
.
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