Number of 1-sided strip polyedges with n cells.

Terms

a(0) =1a(1) =2a(2) =6a(3) =14a(4) =40a(5) =102a(6) =284a(7) =752a(8) =2069a(9) =5547a(10) =15134a(11) =40712a(12) =110456a(13) =297066a(14) =802808a(15) =2156378a(16) =5810329a(17) =15584271a(18) =41894990a(19) =112217372a(20) =301115391a(21) =805584175a(22) =2158366236a(23) =5768337730a(24) =15435275815a(25) =41214200699a(26) =110164972820a(27) =293922598172a(28) =784925297952