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%I #4 Aug 13 2020 14:25:50
%S 2,3,4,5,6,6,7,8,9
%N Numbers k such that the radius of the smallest circle into which A121603(m) unit circles can be packed is 1 + csc(Pi/k).
%C From the diagrams in the link it appears likely that 10,12,12 are the next three terms.
%H E. Friedman, <a href="https://erich-friedman.github.io/packing/cirincir/">Erich's Packing Center: "Circles in Circles"</a>
%e See A121602 for the case a(8) = 9 pertaining to A121603(8) = 11 unit circles.
%Y Cf. A121603, A121570, A121598, A121601, A121602.
%K nonn
%O 0,1
%A _Rick L. Shepherd_, Aug 09 2006