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A140682 A triangle of coefficients of the difference of the GCD and Binomial in a polynomials: p(x,n)=Sum[GCd(n,i)-Binmomial(n,i))*x^i,{i,0,n}]. 0
0, 1, -1, 1, 2, -2, -2, 2, 3, -3, -4, -3, 3, 4, -4, -9, -9, -4, 4, 5, -5, -13, -17, -13, -5, 5, 6, -6, -20, -34, -34, -20, -6, 6, 7, -7, -26, -55, -66, -55, -26, -7, 7, 8, -8, -35, -81, -125, -125, -81, -35, -8, 8, 9, -9, -43, -119, -208, -247, -208, -119, -43, -9, 9 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,5

COMMENTS

Row sums are:

{0, 1, 0, -4, -18, -43, -108, -228, -482, -987};

This is a method of producing symmetrical polynomials that is combinatorial related.

FORMULA

p(x,n)=Sum[GCd(n,i)-Binmomial(n,i))*x^i,{i,0,n}]; a(n,m)=Coefficiencts(p(x,n))

EXAMPLE

{0},

{1, -1, 1},

{2, -2, -2, 2},

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

{4, -4, -9, -9, -4, 4},

{5, -5, -13, -17, -13, -5, 5},

{6, -6, -20, -34, -34, -20, -6, 6},

{7, -7, -26, -55, -66, -55, -26, -7, 7},

{8, -8, -35, -81, -125, -125, -81, -35, -8, 8},

{9, -9, -43, -119, -208, -247, -208, -119, -43, -9, 9}

MATHEMATICA

Clear[p, x, n] p[x_, n_] = Sum[(GCD[n, i] - Binomial[n, i])*x^i, {i, 0, n}]; Table[ExpandAll[p[x, n]], {n, 1, 10}]; a = Table[CoefficientList[p[x, n], x], {n, 1, 10}]; Flatten[a]

CROSSREFS

Cf. A109004.

Sequence in context: A029084 A032229 A024366 * A049317 A134544 A106161

Adjacent sequences:  A140679 A140680 A140681 * A140683 A140684 A140685

KEYWORD

tabl,uned,sign

AUTHOR

Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Jul 11 2008

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Last modified February 15 10:28 EST 2012. Contains 205763 sequences.