OFFSET
1,2
MATHEMATICA
seqA = Table[Round[n/2], {n, 1, 180}] (* A004524 *)
seqB = Table[n, {n, 1, 80}]; (* A000027 *)
jointRank[{seqA_, seqB_}] := {Flatten@Position[#1, {_, 1}],
Flatten@Position[#1, {_, 2}]} &[Sort@Flatten[{{#1, 1} & /@ seqA,
{#1, 2} & /@ seqB}, 1]];
limseqU = FixedPoint[jointRank[{seqA, #1[[1]]}] &, jointRank[{seqA, seqB}]][[1]] (* A187480 *)
Complement[Range[Length[seqA]], limseqU] (* A187481 *)
(* by Peter J. C. Moses, Mar 10 2011 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Mar 10 2011
STATUS
approved