MathDB
Problems
Contests
National and Regional Contests
PEN Problems
PEN P Problems
4
P 4
P 4
Source:
May 25, 2007
Additive Number Theory
Problem Statement
Determine all positive integers that are expressible in the form
a
2
+
b
2
+
c
2
+
c
,
a^{2}+b^{2}+c^{2}+c,
a
2
+
b
2
+
c
2
+
c
,
where
a
a
a
,
b
b
b
,
c
c
c
are integers.
Back to Problems
View on AoPS