Smooth necklaces with 3 colors.

Terms

a(0) =1a(1) =3a(2) =5a(3) =8a(4) =15a(5) =27a(6) =58a(7) =115a(8) =252a(9) =541a(10) =1196a(11) =2629a(12) =5894a(13) =13156a(14) =29667a(15) =66978a(16) =151966a(17) =345497a(18) =788396a(19) =1802678a(20) =4133161a(21) =9495317a(22) =21861393a(23) =50423468a(24) =116514553a(25) =269666605a(26) =625108573a(27) =1451128479a(28) =3373267275a(29) =7851415838