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 A184408 Number of holes in the toothpick structure of A182840. 3
 0, 0, 0, 0, 0, 0, 0, 2, 6, 6, 6, 6, 6, 8, 12, 18, 30, 30, 30, 30, 30, 30, 30, 34, 46, 56, 60, 60, 60, 66, 80, 98, 126, 126, 126, 126, 126, 126, 126, 130, 142, 150, 150, 150, 150, 154, 166, 186, 222, 248, 252, 252, 252, 252, 252, 260, 288, 322, 344, 348, 348, 364, 404, 450, 510, 510, 510, 510, 510, 510, 510, 514, 526 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,8 COMMENTS Each connected group of unoccupied lines in the hexagonal structure enclosed by toothpicks counts as a hole. LINKS Olaf Voß, Table of n, a(n) for n = 0..625 N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS Olaf Voß, Toothpick structures on hexagonal net EXAMPLE Structure after step 8:       \_/     \_/ \_/   \_/ \_/ \_/ \_/  _/ \_  \_/ / \_/ \_/ \_/ \ \_/ \_/ \_/ \_/ / \ / \_/ \ / \ \_/ \_/ \_/ \_/ / \_/ \_/ \_/ \ \_/ \_/ \_/ \_/ / \_  \_/  _/ \   / \_/ \_/ \     / \_/ \       / \ There are 6 holes in this structure, so a(8)=6. CROSSREFS For total number of missing toothpicks see A184409. Sequence in context: A141624 A134413 A134201 * A184409 A137479 A304363 Adjacent sequences:  A184405 A184406 A184407 * A184409 A184410 A184411 KEYWORD nonn AUTHOR Olaf Voß, Jan 13 2011 STATUS approved

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Last modified July 26 20:17 EDT 2021. Contains 346294 sequences. (Running on oeis4.)