Question 170
Find for which
$$
n \in \{3\,900, 3\,901, 3\,902, 3\,903, 3\,904, 3\,905, 3\,906, 3\,907, 3\,908, 3\,909\}
$$
the set $\{1, 2, 3, \dots, n\}$ can be partitioned into (disjoint) triples in such a way that one of the three numbers in any triple is the sum of the other two.
$$
n \in \{3\,900, 3\,901, 3\,902, 3\,903, 3\,904, 3\,905, 3\,906, 3\,907, 3\,908, 3\,909\}
$$
the set $\{1, 2, 3, \dots, n\}$ can be partitioned into (disjoint) triples in such a way that one of the three numbers in any triple is the sum of the other two.