%I M2513 #20 Apr 06 2023 08:34:07
%S 0,3,6,5,12,2,10,9,24,11,4,14,20,15,18,17,48,26,22,21,8,23,28,38,40,
%T 27,30,29,36,50,34,33,96,35,52,62,44,39,42,41,16,74,46,45,56,47,76,86,
%U 80,51,54,53,60,98,58,57,72,59,100,110,68,63,66,65
%N Earliest sequence with a(a(a(n))) = 2n.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Delbert L. Johnson, <a href="/A007479/b007479.txt">Table of n, a(n) for n = 0..19999</a>
%H <a href="/index/Aa#aan">Index entries for sequences of the a(a(n)) = 2n family</a>
%F a(0) = 0, a(2*n) = 2*a(n), a(6*n+1) = 6*n+3, a(6*n+3) = 6*n+5, a(6*n+5) = 12*n+2. - _Sean A. Irvine_, Jan 05 2018
%Y Cf. A002516.
%K easy,nonn,nice
%O 0,2
%A _N. J. A. Sloane_
%E Missing a(48) = 80 inserted by _Sean A. Irvine_, Jan 05 2018