permutohedra
...that the six permutations of the vector (1,2,3) form a hexagon in 3d space, the 24 permutations of (1,2,3,4) form a truncated octahedron in four dimensions, and both are examples of permutohedra?
...that the six <a href="./Permutation" id="mwCfE" rel="mw:WikiLink" title="Permutation">permutations</a> of the <a class="mw-disambig" href="./Vector" id="mwCfI" rel="mw:WikiLink" title="Vector">vector</a> (1,2,3) form a <a href="./Hexagon" id="mwCfM" rel="mw:WikiLink" title="Hexagon">hexagon</a> in <a href="./Euclidean_space" id="mwCfQ" rel="mw:WikiLink" title="Euclidean space">3d space</a>, the 24 permutations of (1,2,3,4) form a <a href="./Truncated_octahedron" id="mwCfU" rel="mw:WikiLink" title="Truncated octahedron">truncated octahedron</a> in <a class="mw-disambig" href="./Fourth_dimension" id="mwCfY" rel="mw:WikiLink" title="Fourth dimension">four dimensions</a>, and both are examples of <b id="mwCfc"><a href="./Permutohedron" id="mwCfg" rel="mw:WikiLink" title="Permutohedron">permutohedra</a></b>?