Number of distinct minimal unary DFA's with exactly n states.

Terms

a(0) =2a(1) =4a(2) =12a(3) =30a(4) =78a(5) =180a(6) =432a(7) =978a(8) =2220a(9) =4926a(10) =10908a(11) =23790a(12) =51750a(13) =111564a(14) =239604a(15) =511758a(16) =1089306a(17) =2309118a(18) =4880946a(19) =10285146a(20) =21619770a(21) =45334776a(22) =94865904a(23) =198116082a(24) =413013684a(25) =859573638a(26) =1786263822a(27) =3706729488a(28) =7681910826