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Problems
Contests
National and Regional Contests
Portugal Contests
Portugal MO
2011 Portugal MO
6
6
Part of
2011 Portugal MO
Problems
(1)
n = not sum of 2 or more consecutive natural numbers
Source: 2011 Portugal (OPM) p6
5/20/2024
The number
1000
1000
1000
can be written as the sum of
16
16
16
consecutive natural numbers:
1000
=
55
+
56
+
.
.
.
+
70.
1000 = 55 + 56 + ... + 70.
1000
=
55
+
56
+
...
+
70.
Determines all natural numbers that cannot be written as the sum of two or more consecutive natural numbers .
number theory
consecutive