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A155993
A triangle of polynomial coefficients: p(x,n)=-(ChebyshevT[n, x] - ((x + 1)^n + (1 - x)^n)); sp(x,n) = p(x, n) + x^n*p(1/x, n).
0
2, 1, 1, 3, 0, 3, -2, 9, 9, -2, -5, 0, 40, 0, -5, -14, 5, 40, 40, 5, -14, -27, 0, 90, 0, 90, 0, -27, -62, 21, 154, 14, 14, 154, 21, -62, -125, 0, 400, 0, -40, 0, 400, 0, -125, -254, 9, 648, 288, -180, -180, 288, 648, 9, -254, -507, 0, 1410, 0, 120, 0, 120, 0, 1410, 0, -507
OFFSET
0,1
COMMENTS
Row sums are:
{2, 2, 6, 14, 30, 62, 126, 254, 510, 1022, 2046,...}.
FORMULA
p(x,n)=-(ChebyshevT[n, x] - ((x + 1)^n + (1 - x)^n));
sp(x,n) = p(x, n) + x^n*p(1/x, n).
EXAMPLE
{2},
{1, 1},
{3, 0, 3},
{-2, 9, 9, -2},
{-5, 0, 40, 0, -5},
{-14, 5, 40, 40, 5, -14},
{-27, 0, 90, 0, 90, 0, -27},
{-62, 21, 154, 14, 14, 154, 21, -62},
{-125, 0, 400, 0, -40, 0, 400, 0, -125},
{-254, 9, 648, 288, -180, -180, 288, 648, 9, -254},
{-507, 0, 1410, 0, 120, 0, 120, 0, 1410, 0, -507}
MATHEMATICA
p[x_, n_] = -(ChebyshevT[n, x] - ((x + 1)^n + (1 - x)^n));
sp[x_, n_] = p[x, n] + x^n*p[1/x, n];
Table[FullSimplify[ExpandAll[sp[x, n]]], {n, 0, 10}];
Table[CoefficientList[FullSimplify[ExpandAll[sp[x, n]]], x], {n, 0, 10}]; Q Flatten[%]
CROSSREFS
Sequence in context: A033774 A033804 A103910 * A353630 A341091 A210806
KEYWORD
sign,tabl,uned
AUTHOR
Roger L. Bagula, Feb 01 2009
STATUS
approved