Number of inseparable type set partitions of {1..n}.

Terms

a(0) =0a(1) =0a(2) =1a(3) =1a(4) =5a(5) =6a(6) =37a(7) =50a(8) =345a(9) =502a(10) =3851a(11) =5897a(12) =49854a(13) =79249a(14) =730745a(15) =1195147a(16) =11915997a(17) =19929390a(18) =213332101a(19) =363275555a(20) =4150104224a(21) =7172334477a(22) =87003759195a(23) =152231458128