- #1
zetafunction
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i have the following conjecture about infinite power series
let be a function f(x) analytic so it can be expanded into a power series
[tex] f(x)= \sum_{n=0}^{\infty} a_{2n}(-1)^{n} x^{2n} [/tex]
with [tex] a_{2n} = \int_{-c}^{c}dx w(x)x^{2n} [/tex] [tex] w(x) \ge 0 [/tex] and [tex] w(x)=w(-x) [/tex] on the whole interval (-c,c) in case c is inifinite this W(x) is ALWAYS positive for every real 'x'
here 'c' is a Real constant , also we can have [tex] c=\infty [/tex]
and [tex] a(n)=0 [/tex] for n=1,3,5,7,9,.. 2n-1
the [tex] a(2n) [/tex] are ALL positive and NONZERO
then f(x) has ONLY real roots or f(x) has NO roots at all (not real or complex)
amazingly it seems true , for example it holds for [tex] sin(x)/x [/tex] the Bessel function of zeroth order [tex] J_0 (x) [/tex] and so on
let be a function f(x) analytic so it can be expanded into a power series
[tex] f(x)= \sum_{n=0}^{\infty} a_{2n}(-1)^{n} x^{2n} [/tex]
with [tex] a_{2n} = \int_{-c}^{c}dx w(x)x^{2n} [/tex] [tex] w(x) \ge 0 [/tex] and [tex] w(x)=w(-x) [/tex] on the whole interval (-c,c) in case c is inifinite this W(x) is ALWAYS positive for every real 'x'
here 'c' is a Real constant , also we can have [tex] c=\infty [/tex]
and [tex] a(n)=0 [/tex] for n=1,3,5,7,9,.. 2n-1
the [tex] a(2n) [/tex] are ALL positive and NONZERO
then f(x) has ONLY real roots or f(x) has NO roots at all (not real or complex)
amazingly it seems true , for example it holds for [tex] sin(x)/x [/tex] the Bessel function of zeroth order [tex] J_0 (x) [/tex] and so on
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