Number of median graphs on n nodes.

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =4a(5) =11a(6) =23a(7) =69a(8) =178a(9) =567a(10) =1741a(11) =5890a(12) =20005a(13) =71294a(14) =257889a(15) =958595