2: 0.501157154491 3: 0.642304940783 4: 0.682378046914 7: 0.772734254637 19: 0.800049447442 37: 0.802365540907 2 3 4 7 19 37 Fit of radii by a power law r = a0*n^a1: a0 = 0.74570 a1 = -0.45676