A214821 Number of genus 0 unsensed hypermaps with n darts.
1, 3, 6, 20, 57, 240, 954, 4566, 22641, 121823, 683307, 4004055
Offset: 1
Links
- Timothy R. Walsh, Space-efficient generation of nonisomorphic maps and hypermaps
- T. R. Walsh, Space-Efficient Generation of Nonisomorphic Maps and Hypermaps, J. Int. Seq. 18 (2015) # 15.4.3