centered octahedral number
... that René Just Haüy modeled octahedral crystals mathematically as polycubes made of a centered octahedral number of cubes ?
... that <a href="./René_Just_Haüy" id="mwArA" rel="mw:WikiLink" title="René Just Haüy">René Just Haüy</a> modeled octahedral crystals mathematically as polycubes made of a <b id="mwArE"><a href="./Centered_octahedral_number" id="mwArI" rel="mw:WikiLink" title="Centered octahedral number">centered octahedral number</a></b> of cubes <i id="mwArM">(pictured)</i>?