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%I #8 Jul 28 2018 10:56:53
%S 0,1,-1,-3,-2,2,3,4,-4,-6,-5,-7,-9,7,5,6,10,8,9,13,11,12,16,14,15,-17,
%T -13,-12,-8,-10,-18,-14,-16,-15,-11,-19,-21,-20,-22,-24,-23,-25,-27,
%U -26,-28,-30,-29,-31,-33,31,23,21,19,17,18,22,20,24,25,26,27,28
%N Sequence of distinct signed integers such that a(1) = 0 and for any n > 0, a(n+1) is of the form a(n) + (-2)^k (where k >= 0) and has the smallest possible absolute value (in case of a tie, minimize k).
%C This sequence is likely to contain every signed integer.
%H Rémy Sigrist, <a href="/A316995/a316995.gp.txt">PARI program for A316995</a>
%e The first terms, alongside the value k such that a(n+1) = a(n) + (-2)^k, are:
%e n a(n) k
%e -- ---- --
%e 1 0 0
%e 2 1 1
%e 3 -1 1
%e 4 -3 0
%e 5 -2 2
%e 6 2 0
%e 7 3 0
%e 8 4 3
%e 9 -4 1
%e 10 -6 0
%e 11 -5 1
%e 12 -7 1
%e 13 -9 4
%e 14 7 1
%e 15 5 0
%e 16 6 2
%e 17 10 1
%e 18 8 0
%e 19 9 2
%e 20 13 1
%o (PARI) See Links section.
%Y Cf. A122803.
%K sign
%O 1,4
%A _Rémy Sigrist_, Jul 18 2018