%I A053560
%S A053560 0,0,0,1,6,14,36,93,252,661,1782,4893,13608,37890,106142,298755,844182,
%T A053560 2391732,6797196,19371684,55348596,158491993,454795398,1307534319,
%U A053560 3765720066,10862647236,31381000560,90780846494,262951692390
%N A053560 Number of ternary Lyndon words of length n with trace 0 and subtrace 
               1 over GF(3).
%H A053560 F. Ruskey, <a href="http://www.theory.csc.uvic.ca/~cos/inf/trs/lyn/Fq/
               lyn_tr_subtr_F3.html">Ternary Lyndon words of given trace and subtrace 
               over GF(3)</a>
%F A053560 (1/n) Sum mu(d) M(n/d, 2, 2); d|n, d=1(3) + (1/n) Sum mu(d) M(n/d, 1, 
               1); d|n, d=2(3), where M(n, t, s) = Sum n!/(i!j!k!); i+j+k=n, j=t(3), 
               k=s(3)
%e A053560 a(4) = 1 = |{ 1122 }|
%Y A053560 Cf. A053548, A053561, A053562, A053563, A053564.
%Y A053560 Sequence in context: A074981 A066510 A036387 this_sequence A119874 A134259 
               A069166
%Y A053560 Adjacent sequences: A053557 A053558 A053559 this_sequence A053561 A053562 
               A053563
%K A053560 nonn
%O A053560 1,5
%A A053560 Frank Ruskey (fruskey(AT)cs.uvic.ca), Jan 17 2000