Number of quasitrivial semigroups on an arbitrary n-element set.

A292932

Number of quasitrivial semigroups on an arbitrary n-element set.

Terms

    a(0) =1a(1) =1a(2) =4a(3) =20a(4) =138a(5) =1182a(6) =12166a(7) =146050a(8) =2003882a(9) =30930734a(10) =530477310a(11) =10007736906a(12) =205965058162

External references