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 A006980 Compositions: 6th column of A048004. (Formerly M1411) 7
 1, 2, 5, 12, 28, 64, 143, 315, 687, 1485, 3186, 6792, 14401, 30391, 63872, 133751, 279177, 581040, 1206151, 2497895, 5161982, 10646564, 21919161, 45052841, 92461171, 189489255, 387830160, 792810956, 1618840800, 3301999647 (list; graph; refs; listen; history; text; internal format)
 OFFSET 6,2 REFERENCES N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). J. L. Yucas, Counting special sets of binary Lyndon words, Ars Combin., 31 (1991), 21-29. LINKS Alois P. Heinz, Table of n, a(n) for n = 6..1000 J. L. Yucas, Counting special sets of binary Lyndon words, Ars Combin., 31 (1991), 21-29. (Annotated scanned copy) Index entries for linear recurrences with constant coefficients, signature (2,1,0,-1,-2,-4,-5,-4,-3,-2,-1). FORMULA G.f.: x^6 / ((1-x-x^2-x^3-x^4-x^5) * (1-x-x^2-x^3-x^4-x^5-x^6)). - Alois P. Heinz, Oct 29 2008 MAPLE a:= n-> (Matrix(11, (i, j)-> if i=j-1 then 1 elif j=1 then [2, 1, 0, -1, -2, -4, -5, -4, -3, -2, -1][i] else 0 fi)^n) [1, 7]: seq(a(n), n=6..40); # Alois P. Heinz, Oct 29 2008 PROG (PARI) Vec(1/(1-x-x^2-x^3-x^4-x^5)/(1-x-x^2-x^3-x^4-x^5-x^6)+O(x^99)) \\ Charles R Greathouse IV, Jan 10 2013 CROSSREFS Sequence in context: A320590 A006979 A019301 * A045623 A290990 A324586 Adjacent sequences:  A006977 A006978 A006979 * A006981 A006982 A006983 KEYWORD nonn,easy AUTHOR EXTENSIONS Corrected definition: 6th column of A048004. - Geoffrey Critzer, Nov 09 2008 STATUS approved

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Last modified October 19 14:54 EDT 2019. Contains 328223 sequences. (Running on oeis4.)