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Problems
Contests
National and Regional Contests
PEN Problems
PEN A Problems
60
60
Part of
PEN A Problems
Problems
(1)
A 60
Source:
5/25/2007
Prove that there exist an infinite number of ordered pairs
(
a
,
b
)
(a,b)
(
a
,
b
)
of integers such that for every positive integer
t
t
t
, the number
a
t
+
b
at+b
a
t
+
b
is a triangular number if and only if
t
t
t
is a triangular number.
Divisibility Theory