Number of disconnected graphs with n nodes.

Terms

a(0) =0a(1) =0a(2) =1a(3) =2a(4) =5a(5) =13a(6) =44a(7) =191a(8) =1229a(9) =13588a(10) =288597a(11) =12297299a(12) =1031342116a(13) =166123498733