OFFSET
0,1
COMMENTS
In strategy (a) we do not count spheres that are generated (by reflection) from quintuples that were not generated in the previous generation.
LINKS
C. L. Mallows, Growing Apollonian Packings, J. Integer Sequences, 12 (2009), article 09.2.1.
EXAMPLE
For a(3), we apply reflection only to the 20 quintuples that were generated in the second generation, ignoring the 10 "extra" quintuples (which will appear as ABA = BAB in the third generation).
CROSSREFS
KEYWORD
hard,more,nonn
AUTHOR
Colin Mallows, Jan 13 2009
STATUS
approved