Number of rooted connected graphs where every block is a complete graph.

Terms

a(0) =0a(1) =1a(2) =1a(3) =3a(4) =8a(5) =25a(6) =77a(7) =258a(8) =871a(9) =3049a(10) =10834a(11) =39207a(12) =143609a(13) =532193a(14) =1990163a(15) =7503471a(16) =28486071a(17) =108809503a(18) =417862340a(19) =1612440612a(20) =6248778642a(21) =24309992576a(22) =94905791606a(23) =371691137827