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A139585 A triangle of coefficients from truncated Pascal binomials in {x,y},y,z}and {z,x} in which the x^n,y^n and z^n terms are deleted: f(x,y,n)=(x+y)^n-(x^n+y^n); p(x,y,z,n)=f(x,y,n)+f(y,z,n)+f(z,x,n). 0
-3, 0, 2, 4, 6, 6, 6, 14, 8, 12, 8, 30, 10, 20, 20, 10, 62, 12, 30, 40, 30, 12, 126, 14, 42, 70, 70, 42, 14, 254, 16, 56, 112, 140, 112, 56, 16, 510, 18, 72, 168, 252, 252, 168, 72, 18, 1022, 20, 90, 240, 420, 504, 420, 240, 90, 20 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Row sums are:

{-3, 0, 6, 18, 42, 90, 186, 378, 762, 1530, 3066};

These polynomials are inspired by the looping hyperfolium projections of the type:

f[x,i,n)=Binomial[n,i]*x^i/(1+x^n);

in n-1 coordinates.

FORMULA

f(x,y,n)=(x+y)^n-(x^n+y^n); p(x,y,z,n)=f(x,y,n)+f(y,z,n)+f(z,x,n); Out_n,m=Coefficients(p(x,1,1,n).

EXAMPLE

{-3},

{0},

{2, 4},

{6, 6, 6},

{14, 8, 12, 8},

{30, 10, 20, 20, 10},

{62, 12, 30, 40, 30, 12},

{126, 14, 42, 70, 70, 42, 14},

{254, 16, 56, 112, 140, 112, 56, 16},

{510, 18, 72, 168, 252, 252, 168, 72, 18},

{1022, 20, 90, 240, 420, 504, 420, 240, 90, 20}

MATHEMATICA

f[x_, y_, n_] := (x + y)^n - x^n - y^n Table[ExpandAll[f[x, y, n] + f[y, z, n] + f[x, z, n]], {n, 0, 10}]; a = Table[CoefficientList[ExpandAll[f[x, y, n] + f[y, z, n] + f[x, z, n]] /. y -> 1 /. z -> 1, x], {n, 0, 10}]; Flatten[a]

CROSSREFS

Sequence in context: A145856 A092154 A177344 * A089598 A117139 A159959

Adjacent sequences:  A139582 A139583 A139584 * A139586 A139587 A139588

KEYWORD

uned,sign

AUTHOR

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

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Last modified February 14 15:32 EST 2012. Contains 205635 sequences.