Partial sums of A122836 (number of topologies on n labeled elements in which at least one element belongs to some pair of noncomparable members of the topology).
A178689
Partial sums of A122836 (number of topologies on n labeled elements in which at least one element belongs to some pair of noncomparable members of the topology).
Terms
- a(0) =0a(1) =0a(2) =0a(3) =10a(4) =253a(5) =6384a(6) =208887a(7) =9673189a(8) =651633791a(9) =63901292323
External references
- oeis: A178689