Number of disconnected regular simple graphs on n vertices with girth at least 6.

Terms

a(0) =0a(1) =0a(2) =1a(3) =1a(4) =2a(5) =1a(6) =2a(7) =1a(8) =2a(9) =1a(10) =2a(11) =1a(12) =3a(13) =2a(14) =4a(15) =3a(16) =5a(17) =4a(18) =7a(19) =6a(20) =9a(21) =9a(22) =12a(23) =12a(24) =17a(25) =17a(26) =22a(27) =24a(28) =31a(29) =32