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 A082009 a(n) is the label of parent node of node n in tree shown in A082007. 3
 0, 0, 1, 3, 3, 1, 6, 6, 2, 9, 9, 2, 12, 12, 4, 15, 15, 16, 18, 18, 16, 21, 21, 17, 24, 24, 17, 27, 27, 4, 30, 30, 31, 33, 33, 31, 36, 36, 32, 39, 39, 32, 42, 42, 5, 45, 45, 46, 48, 48, 46, 51, 51, 47, 54, 54, 47, 57, 57, 5, 60, 60, 61, 63 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 LINKS Ivan Neretin, Table of n, a(n) for n = 1..10000 MATHEMATICA w = {{0}}; a = ConstantArray[0, 254]; Do[k = 2^Floor@Log2[n - 1]; AppendTo[w, Flatten@Table[w[[n - k]] + (2^k - 1) i, {i, 2^k}]]; a[[w[[-1]]]] = Riffle[#, #] &@w[[-2]], {n, 2, 8}]; a (* Ivan Neretin, Mar 12 2017 *) CROSSREFS Sequence in context: A295290 A165202 A010468 * A110640 A143389 A219218 Adjacent sequences:  A082006 A082007 A082008 * A082010 A082011 A082012 KEYWORD nonn,easy AUTHOR N. J. A. Sloane, Oct 06 2009, based on a posting by Steve Witham (sw(AT)tiac.net) to the Math Fun Mailing List, Sep 30 2009 STATUS approved

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Last modified May 14 19:53 EDT 2021. Contains 343903 sequences. (Running on oeis4.)