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A258050 Position of -n in A258047 after deleting the initial 0.

%I A258050 #7 Aug 21 2015 11:03:58
%S A258050 3,6,8,10,12,13,16,18,20,22,24,26,28,30,32,34,35,37,39,40,42,44,46,48,
%T A258050 50,52,54,56,58,60,62,64,66,68,70,72,74,76,78,80,82,84,86,88,90,92,94,
%U A258050 96,98,100,102,104,106,108,110,112,114,116,118,120,122,124
%N A258050 Position of -n in A258047 after deleting the initial 0.
%C A258050 A258047 = (0,1,2,-1,3,6,-7,5,-3,7,...).  Remove the initial 0 to get (1,2,-1,3,6,-7,5,6,-3,7,...), and note that (1,2,3,4,...) occupy positions 1,2,4,7,..., (as in A258049) and that (-1,-2,-3,...) occupy positions 3,6,8,...  (as in A258050).
%H A258050 Clark Kimberling, <a href="/A258050/b258050.txt">Table of n, a(n) for n = 1..1000</a>
%t A258050 {a, f} = {{1}, {0}}; Do[tmp = {#, # - Last[a]} &[Min[Complement[#, Intersection[a, #]]&[Last[a] + Complement[#, Intersection[f, #]] &[Range[2 - Last[a], -1]]]]];
%t A258050 If[! IntegerQ[tmp[[1]]], tmp = {Last[a] + #, #} &[NestWhile[# + 1 &, 1, ! (! MemberQ[f, #] && ! MemberQ[a, Last[a] - #]) &]]];
%t A258050 AppendTo[a, tmp[[1]]]; AppendTo[f, tmp[[2]]], {500}];
%t A258050 -1 + Flatten[Position[Sign[f], 1]]  (* A258049 *)
%t A258050 -1 + Flatten[Position[Sign[f], -1]] (* A258050 *) (* _Peter J. C. Moses_, May 14 2015 *)
%Y A258050 Cf. A258047, A258049 (complement).
%K A258050 nonn,easy
%O A258050 1,1
%A A258050 _Clark Kimberling_, Jun 05 2015