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A140883 A coefficient triangular sequence made from the ChebyshevT polynomials, T(x,n) and their toral inverse (or reversed coefficient) polynomial x^n*T(1/x,n): p(x,n)=T[x,n]+x^n*T(1/x,n). +0
1
2, 1, 1, 1, 0, 1, 4, -3, -3, 4, 9, 0, -16, 0, 9, 16, 5, -20, -20, 5, 16, 31, 0, -30, 0, -30, 0, 31, 64, -7, -112, 56, 56, -112, -7, 64, 129, 0, -288, 0, 320, 0, -288, 0, 129, 256, 9, -576, -120, 432, 432, -120, -576, 9, 256, 511, 0, -1230, 0, 720, 0, 720, 0, -1230, 0, 511 (list; table; graph; listen)
OFFSET

1,1

COMMENT

Row sums are all two.

All this does is make a symmetrical coefficient triangle

since the double integration is no where zero, they aren't orthogonal;

Table[Integrate[p[x, n]*p[x, m]/

Sqrt[1 - x^2], {x, -1, 1}], {n, 0, 10}, {m, 0, 10}]

FORMULA

p(x,n)=T[x,n]+x^n*T(1/x,n); Out_n,m=Coefficients(p(x,n)).

EXAMPLE

{2},

{1, 1},

{1, 0, 1},

{4, -3, -3, 4},

{9, 0, -16, 0, 9},

{16, 5, -20, -20, 5, 16},

{31, 0, -30, 0, -30, 0, 31},

{64, -7, -112, 56, 56, -112, -7, 64},

{129, 0, -288, 0, 320, 0, -288, 0, 129},

{256, 9, -576, -120, 432, 432, -120, -576, 9, 256},

{511, 0, -1230, 0, 720, 0, 720, 0, -1230, 0, 511}

MATHEMATICA

Clear[p, x, n, m, a]; p[x_, n_] := ChebyshevT[n, x] + ExpandAll[x^n*ChebyshevT[n, 1/x]]; Table[p[x, n], {n, 0, 10}]; a = Table[CoefficientList[p[x, n], x], {n, 0, 10}]; Flatten[a]

CROSSREFS

Cf. A053120.

Sequence in context: A068029 A158208 A117274 this_sequence A064744 A135997 A026609

Adjacent sequences: A140880 A140881 A140882 this_sequence A140884 A140885 A140886

KEYWORD

uned,tabl,sign

AUTHOR

Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Jul 22 2008

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Last modified November 27 22:38 EST 2009. Contains 167602 sequences.


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