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[latex]e^{i \pi} + 1 = 0[/latex]
At first, we sample 
in the 
( is odd) equidistant points around 
:
![\[ f_k = f(x_k),\: x_k = x^*+kh,\: k=-\frac{N-1}{2},\dots,\frac{N-1}{2} \]](https://pressbooks.uiowa.edu/app/uploads/quicklatex/quicklatex.com-a227f308e0ceb2dd606be9c841a3e44c_l3.png "Rendered by QuickLaTeX.com")
where 
is some step.
Then we interpolate points 
by polynomial
(1)
Its coefficients 
are found as a solution of system of linear equations:
(2)
Here are references to existing equations: (1), (2).
Here is reference to non-existing equation (??).
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