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A158208 A symmetrical triangle of polynomial coefficients: p(x,n)=If[n == 0, 2, Sum[Binomial[n, i]*(x - 1)^i, {i, 0, Floor[(n - 1)/2]}] + x^n*Sum[ Binomial[n, i]*(1/x - 1)^i, {i, 0, Floor[(n - 1)/2]}]]. 0
2, 1, 1, 1, 0, 1, -2, 3, 3, -2, -3, 4, 0, 4, -3, 6, -15, 10, 10, -15, 6, 10, -24, 15, 0, 15, -24, 10, -20, 70, -84, 35, 35, -84, 70, -20, -35, 120, -140, 56, 0, 56, -140, 120, -35, 70, -315, 540, -420, 126, 126, -420, 540, -315, 70, 126, -560, 945, -720, 210, 0, 210 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

Straight row sums are two, but absolute value row sums are:

{2, 2, 2, 10, 14, 62, 98, 418, 702, 2942, 5122,...}.

FORMULA

p(x,n)=If[n == 0, 2, Sum[Binomial[n, i]*(x - 1)^i, {i, 0, Floor[(n - 1)/2]}] + x^n*Sum[ Binomial[n, i]*(1/x - 1)^i, {i, 0, Floor[(n - 1)/2]}]];

out(n,m)=coefficients(p(x,n)).

EXAMPLE

{2},

{1, 1},

{1, 0, 1},

{-2, 3, 3, -2},

{-3, 4, 0, 4, -3},

{6, -15, 10, 10, -15, 6},

{10, -24, 15, 0, 15, -24, 10},

{-20, 70, -84, 35, 35, -84, 70, -20},

{-35, 120, -140, 56, 0, 56, -140, 120, -35},

{70, -315, 540, -420, 126, 126, -420, 540, -315, 70},

{126, -560, 945, -720, 210, 0, 210, -720, 945, -560, 126}

MATHEMATICA

Clear[p, x, n];

p[x_, n_] = If[ n == 0, 2, Sum[Binomial[ n, i]*(x - 1)^i, {i, 0, Floor[(n - 1)/2]}] + Expand[x^n*Sum[Binomial[n, i]*(1/x - 1)^ i, {i, 0, Floor[(n - 1)/2]}]]];

Table[CoefficientList[p[x, n], x], {n, 0, 10}];

Flatten[%]

CROSSREFS

Sequence in context: A093718 A035212 A068029 * A117274 A140883 A064744

Adjacent sequences:  A158205 A158206 A158207 * A158209 A158210 A158211

KEYWORD

sign,tabl,uned

AUTHOR

Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Mar 13 2009

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Last modified February 15 04:23 EST 2012. Contains 205694 sequences.