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A139144 Triangular sequence of coefficients of central statistical moments as a recursion. c = -(x - x^2); b = (-1 - a + 2 x)/x; a = 0; p(x, n) = (a + b*x)*p(x, n - 1) + c*p(x, n - 2}. 0
1, 0, 0, 1, -1, 0, 1, -3, 2, 0, 1, -4, 6, -3, 0, 1, -5, 10, -10, 4, 0, -1, 6, -15, 20, -15, 5, 0, 1, -9, 33, -65, 75, -49, 14, 0, -1, 12, -58, 152, -240, 234, -132, 33, 0, 1, -15, 92, -310, 642, -854, 724, -360, 80, 0, -1, 18, -135, 564, -1472, 2530, -2906, 2174, -965, 193 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,8

COMMENTS

Row sums: {1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...};

The p(x,0) to p(x,5) are from the MathWorld page and p(x,6) to p(x,10) are recursively generated.

REFERENCES

Charles D. Hodgeman, ed., "CRC Standard Mathematical Tables and Formulae", 12th Edition, page 391

Samuel M. Selby, ed., "CRC Standard Mathematical Tables and Formulae",16th Edition, page 530

Weisstein, Eric W. "Central Moment." http://mathworld.wolfram.com/CentralMoment.html

FORMULA

c = -(x - x^2); b = (-1 - a + 2 x)/x; a = 0; p(x, n) = (a + b*x)*p(x, n - 1) + c*p(x, n - 2}; out_n,m=Coefficients(p(x,n)).

EXAMPLE

{1},

{0},

{0, 1, -1},

{0, 1, -3, 2},

{0, 1, -4, 6, -3},

{0, 1, -5, 10, -10, 4},

{0, -1,6, -15, 20, -15, 5},

{0, 1, -9, 33, -65, 75, -49, 14},

{0, -1, 12, -58, 152, -240, 234, -132, 33},

{0, 1, -15, 92, -310, 642, -854, 724, -360, 80},

{0, -1, 18, -135, 564, -1472, 2530, -2906, 2174, -965, 193}

MATHEMATICA

Clear[p, x, a] p[x, 0] = 1; p[x, 1] = 0; p[x, 2] = -x^2 + x; p[x, 3] = 2*x^3 - 3*x^2 + x; p[x, 4] = -3*x^4 + 6*x^3 - 4*x^2 + x; p[x, 5] = 4*x^5 - 10*x^4 + 10*x^3 - 5*x^2 + x; c = -(x - x^2); b = (-1 - a + 2 x)/x; a = 0; p[x_, n_] := p[x, n] = (a + b*x)*p[x, n - 1] + c*p[x, n - 2]; Table[ExpandAll[p[x, n]], {n, 0, 10}]; a0 = Table[CoefficientList[p[x, n], x], {n, 0, 10}]; Flatten[a0] Table[Apply[Plus, CoefficientList[p[x, n], x]], {n, 0, 10}]

CROSSREFS

Sequence in context: A117406 A151844 A008783 * A081576 A054654 A154477

Adjacent sequences:  A139141 A139142 A139143 * A139145 A139146 A139147

KEYWORD

uned,tabl,sign

AUTHOR

Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Jun 05 2008

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Last modified February 15 18:21 EST 2012. Contains 205835 sequences.