a(1)=1到a(4)=12个多集分区的非同构代表:
{{1}} {{1,1}} {{1,1,1}} {{1,1,1,1}}
{{1,2}} {{1,2,2}} {{1,1,2,2}}
{{1,2,3}} {{1,2,2,2}}
{{1},{1,1}} {{1,2,3,3}}
{{1},{2,2}} {{1,2,3,4}}
{{1},{2,3}} {{1},{1,1,1}}
{{2},{1,2}} {{1},{1,2,2}}
{{1},{2,2,2}}
{{1},{2,3,3}}
{{1},{2,3,4}}
{{2},{1,2,2}}
{{3},{1,2,3}}