Moment Problem: Unique Solution for Power Series g(x)=∑a(n)(-1)^nx^n

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given the sequence (power series) g(x)= \sum_{n\ge 0}a(n)(-1)^{n}x^{n}

if i define a(n)=\int_{n=0}^{\infty}dxf(x)x^{n} (1)

if f(x)>0 on the whole interval (0,\infty) , is the solution to (1) unique ?? , this means that the moment problem for a(n) would have only a solution.
 
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How can we tell you if "the solution to (1)" is unique when there is nothing labeled (1)?

And what does an integral of f(x) have to do with a sum of g(x)?

Frankly, nothing here makes any sense.
 
i meant

is the solution to

<br /> a(n)=\int_{n=0}^{\infty}dxf(x)x^{n} <br />

where a(n) is given but f(x) is unknown UNIQUE is f(x) is positive on the whole interval (0,oo) ? , i mean if the integral equation

<br /> a(n)=\int_{n=0}^{\infty}dxf(x)x^{n} <br />

has ONLY a solution provided f(x) is always positive, thanks.
 
I don't think your integral should start at n=0 should it? Maybe x=0 ...
 
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