Number of equivalence classes with primitive period n of base 3 necklaces, where necklaces are equivalent under rotation and permutation of symbols.

A002075

Number of equivalence classes with primitive period n of base 3 necklaces, where necklaces are equivalent under rotation and permutation of symbols.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =8a(5) =22a(6) =52a(7) =140a(8) =366a(9) =992a(10) =2684a(11) =7404a(12) =20440a(13) =56992a(14) =159440a(15) =448540a(16) =1266080a(17) =3587610a(18) =10195276a(19) =29057520a(20) =83018728a(21) =237737984a(22) =682196948a(23) =1961323740a(24) =5648590728a(25) =16294032160a(26) =47071589778a(27) =136171440600

External references