This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A084618 #17 Jul 09 2025 03:58:20 %S A084618 1,1,1,2,3,4,4,5,7,7,8,8,8,9,10,11,12,13,14,14,15,16,17,19,19,19,20, %T A084618 21,21,22,23,24,24,26,27,27,28,29,30,31,31,32,33,34,35,37,37,37,38,39, %U A084618 40,40,41,42,42,43,44,45,46,47,48,48,49,50,51,52,53,55,55,55,56,57,58,59 %N A084618 Maximum number of circles of area 1 that can be packed in a circle of area n. %C A084618 For most values of n these are only conjectures, supported by numerical results. %D A084618 For list of references given by E. Specht, see corresponding link. %H A084618 Erich Friedman, <a href="https://erich-friedman.github.io/packing/cirincir/">Circles in Circles</a> %H A084618 Hugo Pfoertner, <a href="http://www.randomwalk.de/sequences/a084618.pdf">Minimum area of circle needed to cover n circles of area 1</a> %H A084618 E. Specht, <a href="http://hydra.nat.uni-magdeburg.de/packing/cci/cci.html">The best known packings of equal circles in the unit circle</a> %e A084618 a(4)=2 because a circle of area 4 is the smallest one covering two circles of area 1. %e A084618 a(9)=7 is the arrangement of 6 circles closely packed around another circle. This arrangement fits into a circle that has 3*radius of smaller circles and thus 9*their area. %Y A084618 Cf. A084616, A023393, A084644. %Y A084618 Equivalent sequences for packing into a square: A337020, and equilateral triangle: A337019. %K A084618 hard,nonn %O A084618 1,4 %A A084618 _Hugo Pfoertner_, Jun 01 2003