%I #8 Sep 14 2019 18:19:37
%S 0,0,0,12,32,120,288,784,1792,4284,9600,21824,47520,104832,225792,
%T 487260,1040384,2219520,4699296,9942016,20930400,43994748,92184576,
%U 192843776,402451200,838655400,1744404480,3623423328,7515275040
%N Number of 2n-bead balanced binary strings of fundamental period 2n, rotationally equivalent to reversed complement, inequivalent to reverse and complement.
%H Andrew Howroyd, <a href="/A045669/b045669.txt">Table of n, a(n) for n = 0..200</a>
%F a(n) = 2*n*A045687(n).
%F a(n) = A045664(n) - A045665(n). - _Andrew Howroyd_, Sep 14 2019
%Y Cf. A045664, A045665, A045687.
%K nonn
%O 0,4
%A _David W. Wilson_