Search: id:A124720 Results 1-1 of 1 results found. %I A124720 %S A124720 2,5,16,38,96,220,512,1144,2560,5616,12288,26592,57344,122816,262144, %T A124720 556928,1179648,2490112,5242880,11009536,23068672,48233472,100663296, %U A124720 209713152,436207616,905965568,1879048192,3892305920,8053063680 %N A124720 Number of ternary Lyndon words with exactly two 1's. %C A124720 If the offsets are modified, A124720 to A124723 are the 2nd to 5th Witt transform of A000079 [Moree]. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 08 2008] %H A124720 Pieter Moree, The formal series Witt transform, Discr. Math. no. 295 vol. 1-3 (2005) 143-160. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 08 2008] %F A124720 G.f.: x^3*(2-3 x)/((1-2 x^2)(1- 2x)^2) = (x^2/(1-2x)^2 - x^2/(1-2*x^2))/ 2 %e A124720 a(4) = 5 because 1122, 1123, 1132, 1213, 1133 are all Lyndon words on 3 letters with 2 ones. %Y A124720 Cf. A051168, A027376, A124721, A124722, A124723. %Y A124720 Sequence in context: A053683 A082085 A054971 this_sequence A076958 A163825 A102866 %Y A124720 Adjacent sequences: A124717 A124718 A124719 this_sequence A124721 A124722 A124723 %K A124720 nonn %O A124720 3,1 %A A124720 Mike Zabrocki (zabrocki(AT)mathstat.yorku.ca), Nov 05 2006 Search completed in 0.001 seconds