Number of squarefree graphs on n vertices.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =18a(5) =44a(6) =117a(7) =351a(8) =1230a(9) =5069a(10) =25181a(11) =152045a(12) =1116403a(13) =9899865a(14) =104980369a(15) =1318017549a(16) =19427531763a(17) =333964672216