2: 0.520899741122
    3: 0.680174761588
    6: 0.729009112318
    7: 0.850510631038
   19: 0.864658683029
   37: 0.874010778291
   61: 0.880115229685
   91: 0.884348711494
  127: 0.887441584201
  169: 0.889795024392
  217: 0.891643889700
  271: 0.893133838164
  331: 0.894359688882
  397: 0.895385703621
  469: 0.896256928479
  547: 0.897005853508
  631: 0.897656491021
  721: 0.898226965362
  817: 0.898731210027
  919: 0.899180110835
 1027: 0.899582294846
 1141: 0.899944686616
 1261: 0.900272907959

2 3 6 7 19 37 61 91 127 169 217 271 331 397 469 547 631 721 817 919 1027 1141 1261

Fit of radii by a power law r = a0*n^a1:
  a0 = 0.75347  a1 = -0.47876