Is the sum of this series correct?

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opticaltempest
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I am given the following series and its sum
[tex] \sum\limits_{n = 1}^\infty {\frac{1}{{\left( {2n - 1} \right)^2 }}} = \frac{{\pi ^2 }}{8}[/tex]
I need to find the sum of this series
[tex] \sum\limits_{n = 3}^\infty {\frac{1}{{\left( {2n - 1} \right)^2 }}} [/tex]

Is the method I used below this the correct approach? Is there a better or different way?

From the first series where n=1 we have,

[tex] a_n = \frac{1}{{\left( {2n - 1} \right)^2 }}[/tex]

[tex] = {\rm{\{ 1, 1/9, 1/25, }}...{\rm{\} }}[/tex]

Therefore I concluded that we can subtract off the first two terms of
the above sequence to get the sum when n starts at 3. Hence,

[tex] \sum\limits_{n = 3}^\infty {\frac{1}{{\left( {2n - 1} \right)^2 }}} = \frac{{\pi ^2 }}{8} - 1 - \frac{1}{9}[/tex]
 
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