brono[7], obron[7], oboro[7],
obco[7], bono[6], obon[6], bron[6], boro[6], robo[6], coro[5], noro[4],
cob[6], bon[5], bor[5], rob[5], noc[4], ono[3], nor[3], oro[3],
bo[4], co[3], no[2], on[2], or[2], ro[2],