Organizational patterns are known as the basis for Agile software development movement. Patterns usually form a network having relationships among them to support users understand and utilize patterns efficiently and effectively. However little is known about the nature of pattern networks, such as how are organizational patterns different from other patterns from the viewpoint of centrality. To clarify such characteristics, we mine a network consisting 285 patterns including 15 organizational patterns from an existing online pattern repository called Portland Pattern Repository. By applying network analysis techniques to the mined network, we revealed several interesting characteristics of the pattern network and organizational patterns such as that the degree centrality seems to somewhat reflect the commonness and generality of the corresponding pattern.