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%I #11 Oct 24 2019 16:24:57
%S 0,0,1,2,7,23,78,311,1297,6200,31747,178703,1070388,6842898,46158435,
%T 327718768,2437732593,18948528721,153498234770,1293122838953,
%U 11306474635818,102425551817363,959826751122645,9290811889272509,92771812680385087,954447072777977556
%N Number of length n primitive (period n) bracelet structures which are not periodic palindromes using an infinite alphabet.
%C Equivalently, the number of length n bracelet structures that do not have any symmetry under the action of the dihedral group. The corresponding sequence for necklace structures that do not have any symmetry under the action of the cyclic group is A060223.
%H Andrew Howroyd, <a href="/A328035/b328035.txt">Table of n, a(n) for n = 1..200</a>
%F a(n) = A276548(n) - A285042(n).
%e For n = 5, the 7 bracelet structures have the patterns AAABC, AABAC, AABBC, ABABC, AABCD, ABACD, ABCDE.
%o (PARI) \\ Requires T from A309784.
%o seq(n)={my(A=T(n)); vector(n, i, vecsum(A[i, ]))}
%Y Row sums of A309784.
%Y Cf. A060223, A276548, A285042.
%K nonn
%O 1,4
%A _Andrew Howroyd_, Oct 02 2019