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A090639 a(0) = 0; a(2n) = 3*a(n), a(2n+1) = a(n) + 1. 2
0, 1, 3, 2, 9, 4, 6, 3, 27, 10, 12, 5, 18, 7, 9, 4, 81, 28, 30, 11, 36, 13, 15, 6, 54, 19, 21, 8, 27, 10, 12, 5, 243, 82, 84, 29, 90, 31, 33, 12, 108, 37, 39, 14, 45, 16, 18, 7, 162, 55, 57, 20, 63, 22, 24, 9, 81, 28, 30, 11, 36, 13, 15, 6, 729, 244, 246, 83, 252, 85, 87, 30, 270, 91 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..73.

N. J. A. Sloane and J. A. Sellers, On non-squashing partitions, Discrete Math., 294 (2005), 259-274.

MAPLE

S := 3; f := proc(n) global S; option remember; if n=0 then RETURN(0); fi; if n mod 2 = 0 then RETURN(S*f(n/2)); else f((n-1)/2)+1; fi; end;

MATHEMATICA

a[0] = 0; a[n_] := a[n] = If[EvenQ[n], 3*a[n/2], a[(n - 1)/2] + 1];

Table[a[n], {n, 0, 73}] (* Jean-Fran├žois Alcover, Jan 18 2018 *)

CROSSREFS

Cf. A087808, A090640.

Sequence in context: A104005 A224578 A134562 * A294370 A325984 A178774

Adjacent sequences:  A090636 A090637 A090638 * A090640 A090641 A090642

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Dec 14 2003

STATUS

approved

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Last modified November 12 07:03 EST 2019. Contains 329052 sequences. (Running on oeis4.)