Number of 2n-bead balanced binary necklaces of fundamental period 2n equivalent to reverse.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =4a(5) =5a(6) =17a(7) =19a(8) =64a(9) =68a(10) =245a(11) =251a(12) =900a(13) =923a(14) =3411a(15) =3425a(16) =12800a(17) =12869a(18) =48532a(19) =48619a(20) =184500a(21) =184735a(22) =705179a(23) =705431a(24) =2703168a(25) =2704150a(26) =10399675a(27) =10400530a(28) =40113164a(29) =40116599