Number of non-isomorphic connected set-systems of weight n.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =4a(5) =7a(6) =18a(7) =37a(8) =96a(9) =239a(10) =658a(11) =1810a(12) =5358a(13) =16057a(14) =50373a(15) =161811a(16) =536964a(17) =1826151a(18) =6380481a(19) =22822280a(20) =83587920a(21) =312954111a(22) =1197178941a(23) =4674642341a(24) =18620255306a(25) =75606404857a(26) =312763294254