Number of topologies on an n-set X such that for all x in X there is a y in X such that x and y are topologically indistinguishable.
A280202
Number of topologies on an n-set X such that for all x in X there is a y in X such that x and y are topologically indistinguishable.
Terms
- a(0) =1a(1) =0a(2) =1a(3) =1a(4) =10a(5) =31a(6) =361a(7) =2164a(8) =32663a(9) =313121a(10) =6199024a(11) =86219497a(12) =2225685925a(13) =42396094690
External references
- oeis: A280202