Search: id:A143611 Results 1-1 of 1 results found. %I A143611 %S A143611 1,1,2,3,4,6,8,11,14,18,23,29,36,45,55,67,82,99,120,144,173,207,247,295, %T A143611 351,417,495,587,695,823,973,1150,1358,1603,1892,2231,2631,3101,3654, %U A143611 4305,5071,5972,7032,8279,9746,11472,13502,15891,18700,22005,25893 %N A143611 Coefficient expansion sequence of symmetric polynomial: p(x)=1 - x - x^2 + x^4 + x^8 - x^10 - x^11 + x^12. %C A143611 A factor of Lehmer's polynomial from a 12th degree symmetrical polynomial census:(x-1)^2 times Lehmer's polynomial. %C A143611 Vector matrix Markov that gives the same sequence is: %C A143611 CompanionMatrix[p_, x_] := Module[{cl = CoefficientList[p, x], deg, %C A143611 m}, cl = Drop[cl/Last[cl], -1]; deg = Length[cl]; If[deg == 1, {-cl}, %C A143611 m = RotateLeft[IdentityMatrix[deg]]; m[[ -1]] = -cl; Transpose[m]]]; %C A143611 M = Transpose[CompanionMatrix[1 - x - x^2 + x^4 + x^8 - x^10 - x^11 + x^12, x]]; %C A143611 v[0] = Table[a[[n]], {n, 1, 12}]; %C A143611 v[n_] := v[n] = M.v[n - 1]; %C A143611 Table[v[n][[1]], {n, 0, 50}] %F A143611 p(x)=1 - x - x^2 + x^4 + x^8 - x^10 - x^11 + x^12; a(n)=Coefficient_expansion(x^12*p(1/ x)) %F A143611 G.f.: x/((1-x)^2(1+x-x^3-x^4-x^5-x^6-x^7+x^9+x^10)). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 01 2008] %t A143611 f[x_] = 1 - x - x^2 + x^4 + x^8 - x^10 - x^11 + x^12; g[x] = ExpandAll[x^12*f[1/ x]]; a = Table[SeriesCoefficient[Series[1/g[x], {x, 0, 50}], n], {n, 0, 50}]; %Y A143611 Sequence in context: A114829 A007279 A034891 this_sequence A062464 A053270 A003412 %Y A143611 Adjacent sequences: A143608 A143609 A143610 this_sequence A143612 A143613 A143614 %K A143611 nonn %O A143611 1,3 %A A143611 Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Oct 26 2008 Search completed in 0.001 seconds