Total number of subsets of X that are both open and closed summed over all distinct topological spaces X that can be placed on an n-set.
A281547
Total number of subsets of X that are both open and closed summed over all distinct topological spaces X that can be placed on an n-set.
Terms
- a(0) =1a(1) =2a(2) =10a(3) =82a(4) =1038a(5) =19754a(6) =561778a(7) =23890766a(8) =1516425978a(9) =142478603490
External references
- oeis: A281547