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%I #17 Apr 20 2023 10:42:07
%S 0,1,2,3,4,12,13,14,15,16,48,49,50,51,52,60,61,62,63,64,192,193,194,
%T 195,196,204,205,206,207,208,240,241,242,243,244,252,253,254,255,256,
%U 768,769,770,771,772,780,781,782,783,784,816,817,818,819,820,828,829
%N Greedy sequence such that no term is the average of three others.
%D Related to R. K. Guy, Unsolved Problems Number Theory, C16.
%H J. W. Layman, <a href="https://cs.uwaterloo.ca/journals/JIS/LAYMAN/layman.html">Some Properties of a Certain Nonaveraging Sequence</a>, J. Integer Sequences, Vol. 2, 1999, #4.
%H A. M. Odlyzko and R. P. Stanley, <a href="http://www-math.mit.edu/~rstan/papers/od.pdf">Some curious sequences constructed with the greedy algorithm</a>, 1978.
%t Flatten[Outer[Plus, 4 FromDigits[#, 4] & /@ Tuples[{0, 3}, 5], Range[0, 4]]] (* _Birkas Gyorgy_, May 27 2011 *)
%K nonn
%O 1,3
%A _John W. Layman_