Bijection between Standard Young Tableaux of height $\leq 2$ and $\lfloor n/2 \rfloor$-element subsets of $[n]$.

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In OEIS sequence A001405, Mike Zabrocki claims that the number of Standard Young Tableaux of length $\leq 2$ is equal to $\binom{n}{\lfloor n/2 \rfloor}$.

I haven't been able to conjure up a bijection. Is there a standard bijection to know about?