Number of 2n-bead balanced binary strings, rotationally equivalent to reverse.

Terms

a(0) =1a(1) =2a(2) =6a(3) =8a(4) =38a(5) =52a(6) =216a(7) =268a(8) =1062a(9) =1232a(10) =4956a(11) =5524a(12) =21848a(13) =24000a(14) =95780a(15) =102808a(16) =410662a(17) =437548a(18) =1748592a(19) =1847524a(20) =7384988a(21) =7759144a(22) =31033404a(23) =32449828a(24) =129774936a(25) =135207552a(26) =540807104a(27) =561629852a(28) =2246432996a(29) =2326762744