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%I #15 Jan 17 2020 16:02:33
%S 5,4,5,1,5,1,0,4,2,1,2,2,5,7,2,6,8,7,5,9,3,8,0,7,7,1,8,3,3,7,3,4,8,6,
%T 9,6,3,8,4,3,5,5,5,7,4,9,7,3,4,6,4,7,5,2,9,2,5,3,5,6,8,1,6,5,2,1,4,4,
%U 4,1,2,6,8,7,7,7,5,2,2,9,5,9,9,2,4,7,9,4,4,6,4,6,6,2,5,6,2,7,8,9,5
%N Decimal expansion of r_8, the 8th smallest radius < 1 for which a compact packing of the plane exists, with disks of radius 1 and r_8.
%H Steven R. Finch, <a href="http://arxiv.org/abs/2001.00578">Errata and Addenda to Mathematical Constants</a>, p. 62.
%F 3rd root of x^8 - 8x^7 - 44x^6 - 232x^5 - 482x^4 - 24x^3 + 388x^2 - 120x + 9.
%e 0.5451510421225726875938077183373486963843555749734647529253568...
%t RealDigits[Root[x^8 - 8x^7 - 44x^6 - 232x^5 - 482x^4 - 24x^3 + 388x^2 - 120x + 9, x, 3], 10, 101] // First
%Y Cf. A246723 (r_1), A246724 (r_2), A246725 (r_3), A246726 (r_4), A246727 (r_5), A002193 (r_6 = sqrt(2)-1), A246728 (r_7), A246730 (r_9).
%K nonn,cons,easy
%O 0,1
%A _Jean-François Alcover_, Sep 02 2014