content_image/336298.jpg content_image/336292.jpg content_image/336293.jpg content_image/336299.jpg content_image/336294.jpg content_image/336295.jpg content_image/336296.jpg content_image/336297.jpg
Performance Scientific Computing Center (HSCC) of the Beijing Normal University. 

## Appendix: Expressions of A,B,C 

In this Appendix we list constants A, B, C computed using the computer algorithm as described in Sec. III. The condition (3) holds for for ferromagnetic Potts models with v, m, q > 0. This confirms that qA = C is the exact critical frontier in the ferromagnetic regime. 

## 1. Potts model on $^{n}$× n subnets with pure 2-site coupling K 

<img src='content_image/336298.jpg'>

Subnet $^{1}$× 1: 

Subnet $^{2}$× 2: 

<img src='content_image/336292.jpg'>

<img src='content_image/336293.jpg'>

<img src='content_image/336299.jpg'>

<img src='content_image/336294.jpg'>

Subnet $^{3}$× 3: 

<img src='content_image/336295.jpg'>

<img src='content_image/336296.jpg'>

<img src='content_image/336297.jpg'>

