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 A253771 First differences of A253770. 2
 0, 6, 18, 18, 54, 18, 54, 54, 126, 54, 54, 54, 126, 90, 126, 162, 306, 162, 54, 54, 126, 90, 126, 162, 306, 198, 126, 162, 306, 306, 342, 414, 702, 486, 126, 54, 126, 90, 126, 162, 306, 198, 126, 162, 306, 306, 342, 414, 702, 522, 198, 162 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Number of cells turned "ON" at n-th stage of cellular automaton of A253770. Also 6 times the number of Y-toothpicks added at n-th stage in the Y-toothpick structure of A160120. LINKS N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS FORMULA a(n) = 6*A160121(n). EXAMPLE Positive terms can be written as a triangle in which row lengths is A011782 as shown below: 6; 18; 18,  54; 18,  54,54,126; 54,  54,54,126,90,126,162,306; 162, 54,54,126,90,126,162,306,198,126,162,306,306,342,414,702; 486,126,54,126,90,126,162,306,198,126,162,306,306,342,414,702,522,198,162,... CROSSREFS Cf. A139251, A147582, A151724, A160121, A161645, A182633, A250301, A253770. Sequence in context: A174904 A074390 A255617 * A223218 A045857 A074791 Adjacent sequences:  A253768 A253769 A253770 * A253772 A253773 A253774 KEYWORD nonn,tabf AUTHOR Omar E. Pol, Jan 13 2015 STATUS approved

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Last modified November 16 21:47 EST 2018. Contains 317275 sequences. (Running on oeis4.)