echem[9],
efem[9], mech[8], eche[7], hece[7], emce[6],
fee[7], che[6], ech[6], hec[6], hem[6], ehe[5], mee[4],
ef[6], fe[6], hm[5], eh[4], he[4], ce[3], em[3], me[3], ee[2],
