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1988 All Soviet Union Mathematical Olympiad
475
ASU 475 All Soviet Union MO 1988 composites in 1^1, 1^1+2^2, 1^1+2^2+3^3, ...
ASU 475 All Soviet Union MO 1988 composites in 1^1, 1^1+2^2, 1^1+2^2+3^3, ...
Source:
August 8, 2019
number theory
Composite
Problem Statement
Show that there are infinitely many odd composite numbers in the sequence
1
1
,
1
1
+
2
2
,
1
1
+
2
2
+
3
3
,
1
1
+
2
2
+
3
3
+
4
4
,
.
.
.
1^1, 1^1 + 2^2, 1^1 + 2^2 + 3^3, 1^1 + 2^2 + 3^3 + 4^4, ...
1
1
,
1
1
+
2
2
,
1
1
+
2
2
+
3
3
,
1
1
+
2
2
+
3
3
+
4
4
,
...
.
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