Number of nonequivalent monoids of order n with more than one invertible element.

A151823

Number of nonequivalent monoids of order n with more than one invertible element.

Terms

    a(0) =0a(1) =1a(2) =2a(3) =9a(4) =30a(5) =213a(6) =1757a(7) =22956a(8) =955569a(9) =1853259264

External references