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 A222181 Number of pentagons added at n-th stage to the structure of A222180. 4
 0, 1, 5, 10, 10, 10, 20, 30, 20, 10, 20, 40, 40, 30, 50, 70, 40, 10, 20, 40, 60, 80 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Essentially the first differences of A222180. Also number of P-toothpicks added at n-th stage to the P-toothpick structure of A222180. LINKS N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS FORMULA a(n) = 10*A222173(n-2), n >= 3. - Omar E. Pol, Nov 24 2013 EXAMPLE Apparently this is an irregular triangle: 0; 1; 5; 10,10; 10,20,30,20; 10,20,40,40,30,50,70,40; 10,20,40,60,80,... CROSSREFS Cf. A139250, A139251, A147582, A151724, A152968, A161645, A182633, A182841, A222173, A222177, A222180. Sequence in context: A135912 A200990 A040020 * A282172 A123337 A038671 Adjacent sequences:  A222178 A222179 A222180 * A222182 A222183 A222184 KEYWORD nonn,tabf,more AUTHOR Omar E. Pol, Mar 15 2013 STATUS approved

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Last modified August 3 10:49 EDT 2020. Contains 336198 sequences. (Running on oeis4.)