A082009 - OEIS

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A082009

a(n) is the label of parent node of node n in tree shown in A082007.

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