OFFSET
1,5
COMMENTS
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
The packing density, a(n)/n, approaches sqrt(3)*Pi/6 (approximately 0.9069) as n tends to infinity.
LINKS
Erich Friedman, Circles in Triangles
Wikipedia, Circle packing in an equilateral triangle
FORMULA
Limit_{n->oo} a(n)/n = A093766.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Ya-Ping Lu, Nov 05 2020
EXTENSIONS
Terms corrected by Andrew Howroyd and Peter Munn, Apr 23 2023
STATUS
approved