Number of necklaces with n beads of 2 colors, allowing turning over (these are also called bracelets).

A000029

Number of necklaces with n beads of 2 colors, allowing turning over (these are also called bracelets).

Terms

    a(0) =1a(1) =2a(2) =3a(3) =4a(4) =6a(5) =8a(6) =13a(7) =18a(8) =30a(9) =46a(10) =78a(11) =126a(12) =224a(13) =380a(14) =687a(15) =1224a(16) =2250a(17) =4112a(18) =7685a(19) =14310a(20) =27012a(21) =50964a(22) =96909a(23) =184410a(24) =352698a(25) =675188a(26) =1296858a(27) =2493726a(28) =4806078a(29) =9272780

External references