Number of nonisomorphic systems enumerated by A334254; that is, the number of inequivalent closure operators on a set of n elements where all singletons are closed.
A355517
Number of nonisomorphic systems enumerated by A334254; that is, the number of inequivalent closure operators on a set of n elements where all singletons are closed.
Terms
- a(0) =1a(1) =2a(2) =1a(3) =4a(4) =50a(5) =7443a(6) =95239971
External references
- oeis: A355517