Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An ultraspherical spectral method for linear Fredholm and Volterra
  integro-differential equations of convolution type   The Legendre-based ultraspherical spectral method for ordinary differential
equations is combined with a formula for the convolution of two Legendre series
to produce a new technique for solving linear Fredholm and Volterra
integro-differential equations with convolution-type kernels. When the kernel
and coefficient functions are sufficiently smooth then the method is
spectrally-accurate and the resulting almost-banded linear systems can be
solved with linear complexity.

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The categories of this paper are: astro-ph
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The categories of this paper are: alg-geom
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
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The categories of this paper are: hep-ph
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The categories of this paper are: cs
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
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The categories of this paper are: cmp-lg
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The categories of this paper are: supr-con
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The categories of this paper are: q-fin
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The categories of this paper are: hep-th
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-ex
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The categories of this paper are: quant-ph