104种24阶环
gap> NumberSmallRings(18);
0
gap> NumberSmallRings(24);
0
390种16阶环
gap> NumberSmallRings(16);
0//应该是390
16阶循环环共有T(16)=|{1,2,4,8,16}|=5种,特征都为16。
R16_1=Z/256Z_=M_16
R16_2=Z/32Z_
R16_3=Z/48Z_=Z/16Z=Z/16Z_
R16_4=Z/64Z_
R16_5=Z/128Z_
R16_1：2有零因子交换无幺环,1,0,16,1,15,15,256,15,16
R16_2：2有零因子交换无幺环,1,0
