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A026371 a(n) = least k such that s(k) = n, where s = A026370.

%I A026371 #15 Aug 19 2025 06:07:07
%S A026371 1,2,3,5,6,8,9,11,12,13,14,16,17,19,20,21,22,24,25,27,28,29,30,32,33,
%T A026371 35,36,38,39,41,42,43,44,46,47,49,50,51,52,54,55,57,58,60,61,63,64,65,
%U A026371 66,68,69,71,72,73,74,76,77,79,80,82,83,85,86
%N A026371 a(n) = least k such that s(k) = n, where s = A026370.
%C A026371 Complement of A026372; also the rank transform (as at A187224) of (A004526 after removal of its first term, leaving 0,1,1,2,2,3,3,4,4,5,5,6,6,...). - _Clark Kimberling_, Mar 10 2011
%t A026371 seqA = Table[Floor[n/2], {n, 1, 180}]  (* A004526 *)
%t A026371 seqB = Table[n, {n, 1, 80}];           (* A000027 *)
%t A026371 jointRank[{seqA_, seqB_}] := {Flatten@Position[#1, {_, 1}],
%t A026371 Flatten@Position[#1, {_, 2}]} &[Sort@Flatten[{{#1, 1} & /@ seqA,
%t A026371 {#1, 2} & /@ seqB}, 1]];
%t A026371 limseqU = FixedPoint[jointRank[{seqA, #1[[1]]}] &, jointRank[{seqA, seqB}]][[1]]                                   (* A026371 *)
%t A026371 Complement[Range[Length[seqA]], limseqU]  (* A026372 *)
%t A026371 (* by _Peter J. C. Moses_, Mar 10 2011 *)
%Y A026371 Cf. A187422, A026372, A004526.
%K A026371 nonn
%O A026371 1,2
%A A026371 _Clark Kimberling_