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%I #19 Aug 29 2020 02:36:13
%S 0,0,0,0,0,0,1,0,0,0,2,0,1,1,0,0,1,0,2,0,2,1,0,0,0,2,0,1,1,0,4,3,1,0,
%T 0,0,0,0,0,2,1,0,1,4,3,1
%N Experimental values for maximal number of "loose" circles in packing equal circles into a square.
%D H. T. Croft, K. J. Falconer and R. K. Guy: Unsolved problems in geometry, Springer, New York, 1991.
%H D. Boll, <a href="https://web.archive.org/web/20030211053857/http://www.frii.com/~dboll/packing.html">Optimal Packing Of Circles And Spheres</a>
%H E. Friedman, <a href="https://erich-friedman.github.io/packing/index.html">Erich's Packing Center</a>
%H C. D. Maranas, C. A. Floudas and P. M. Pardalos, <a href="https://doi.org/10.1016/0012-365x(93)e0230-2">New results in the packing of equal circles in a square</a>, Discrete Mathematics 142 (1995), p. 287-293.
%H K. J. Nurmela and Patric R. J. Östergård, <a href="https://doi.org/10.1007/PL00009306">Packing up to 50 equal circles in a square</a>, Discrete Comput. Geom. 18 (1997) 1, p. 111-120.
%H E. Specht, <a href="http://www.packomania.com/">www.packomania.com</a>
%K nonn
%O 1,11
%A Eckard Specht (eckard.specht(AT)physik.uni-magdeburg.de)
%E I do not know how many of these values have been rigorously proved. - _N. J. A. Sloane_