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The Fuchsian differential equation of the square lattice Ising model $χ(3)$ susceptibility

N. Zenine·S. Boukraa·S. Hassani·J-M. Maillard
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Abstract

Using an expansion method in the variables $ x_i$ that appear in the $(n-1)$-dimensional integrals representing the $n$-particle contribution to the Ising square lattice model susceptibility $χ$, we generate a long series of coefficients for the 3-particle contribution $χ^{(3)}$, using a $ N^4$ polynomial time algorithm. We give the Fuchsian differential equation of order seven for $χ^{(3)}$ that reproduces all the terms of our long series. An analysis of the properties of this Fuchsian differential equation is performed.

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N. Zenine, S. Boukraa, S. Hassani, J-M. Maillard. 2004-07-26. The Fuchsian differential equation of the square lattice Ising model $χ(3)$ susceptibility. https://doi.org/10.1088/0305-4470/37/41/004

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