<s>[INST] Let \( \mathcal{S} = \{ 1,2,3,4,5,6,7 \} \) be a set with seven elements. Find a subset \( \mathcal{T} \) of \( \mathcal{S} \) with the maximum number of elements such that no two elements of \( \mathcal{T} \) add up to \( 8 \).[/INST]