%I #39 Apr 25 2023 11:17:02
%S 0,1,1,1,3,3,4,6,6,6,7,8,10,10,10,11,12,13,15
%N Maximum number of circles with unit area that can be packed into an equilateral triangle with an area of n.
%C Are a(17) = 12 and a(18) = 13 proved? They look likely to be no more difficult to prove than some of the earlier terms, and are demonstrably lower bounds by the figures in the Friedman link. - _Peter Munn_, Apr 25 2023
%C The packing density, a(n)/n, approaches sqrt(3)*Pi/6 (approximately 0.9069) as n tends to infinity.
%H Erich Friedman, <a href="https://erich-friedman.github.io/packing/cirintri/">Circles in Triangles</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Circle_packing_in_an_equilateral_triangle">Circle packing in an equilateral triangle</a>
%F Limit_{n->oo} a(n)/n = A093766.
%Y Cf. A093766, A269110.
%K nonn,more
%O 1,5
%A _Ya-Ping Lu_, Nov 05 2020
%E Terms corrected by _Andrew Howroyd_ and _Peter Munn_, Apr 23 2023