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%I #8 Apr 11 2014 00:11:26
%S 1,3,2,5,9,4,10,8,15,7,16,6,17,14,26,13,27,12,28,11,29,25,20,39,19,40,
%T 18,41,35,59,34,60,33,61,32,62,31,24,56,23,57,22,58,21,59,51,42,81,71,
%U 111,70,112,69,113,68,114,67,115,66,55,43,30,80,131,79,65,50,103,49,104
%N A variation on Recamán's sequence A005132: see Comments for definition.
%C Sequences A169748-A169752 have the same structure. We start with two sequences A and B. Sequence A is taken to be 1,2,3,4,5,6,7,..., while sequence B varies.
%C Here sequence B is also 1,2,3,4,5,6,7,....
%C We start with the first term of sequence A (which is 1).
%C To extend the sequence, we first try to subtract the next term of A from the current term, but that is allowed only if the result is a positive number not already in the sequence.
%C If that fails, we next try to subtract the next term of B from the current term, but again that is allowed only if the result is a positive number not already in the sequence.
%C Finally, if that fails, we add the next term of A to the current term (this may produce repeated terms, but that is allowed at this step).
%e Start with 1 from A,
%e add 2 from A getting 3,
%e subtract 1 from B getting 2,
%e add 3 from A getting 5,
%e add 4 from A getting 9,
%e subtract 5 from A getting 4,
%e add 6 from A getting 10,
%e subtract 2 from B getting 8,
%e add 7 from A getting 15,
%e add 9 from A getting 16,
%e subtract 10 from A getting 6,
%e add 11 from A getting 17,
%e subtract 3 from B getting 14,
%e add 12 from A getting 26,
%e subtract 13 from A getting 13, ...
%Y Cf. A005132, A169749-A169752, A169755.
%K nonn
%O 1,2
%A _Rodolfo Kurchan_, Apr 08 2010
%E Extended by _D. S. McNeil_, May 09 2010
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