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2020-IMOC
N1
N1
Part of
2020-IMOC
Problems
(1)
Integer equation
Source: IMOC 2020
9/4/2020
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N
1.
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<span class='latex-bold'>N1.</span>
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Find all nonnegative integers
a
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,
c
a,b,c
a
,
b
,
c
such that \begin{align*} a^2+b^2+c^2-ab-bc-ca = a+b+c \end{align*} Proposed by usjl
IMOC
equation
Integer
number theory