Seeding the Spatial Prisoner’s Dilemma with Ulam’s Spiral

Figure 3

Highlighting the location of clusters indicates the configurations in Ulam’s spiral from which cooperator growth occur. Cells in transparent cyan overlay the original configuration of cooperators (dark teal cells) that result in growing clusters of cooperators when and . Figure 3, in sum, spotlights unique locations in Ulam’s spiral. Cooperators’ survival at the locations displayed in Figure 3 following initial collapse of cooperation (see Figure 2) implies that the spatial orientations of cooperators at the surviving locations are unique (vis-à-vis all other locations on the grid), thus hinting at the existence of rare features of Ulam’s spiral at these locations.