Mian–Chowla sequence

In mathematics, the Mian–Chowla sequence is an integer sequence defined recursively in the following way. The sequence starts with

Then for ${\displaystyle n>1}$, ${\displaystyle a_{n}}$ is the smallest integer such that the pairwise sum

is distinct, for all ${\displaystyle i}$ and ${\displaystyle j}$ less than or equal to ${\displaystyle n}$.

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