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A187681
Rank transform of the sequence floor(n/3); complement of A187682.
2
1, 2, 3, 4, 5, 7, 8, 9, 11, 12, 13, 15, 16, 17, 19, 20, 21, 23, 24, 25, 26, 27, 28, 30, 31, 32, 34, 35, 36, 38, 39, 40, 41, 42, 43, 45, 46, 47, 49, 50, 51, 53, 54, 55, 56, 57, 58, 60, 61, 62, 64, 65, 66, 68, 69, 70, 71, 72, 73, 75, 76, 77, 79, 80, 81, 83, 84, 85, 86, 87, 88, 90, 91, 92, 94, 95, 96, 98, 99, 100, 102, 103, 104, 106, 107, 108, 110, 111, 112, 113, 114, 115, 117, 118, 119, 121, 122
OFFSET
1,2
COMMENTS
See A187224.
MATHEMATICA
seqA = Table[Floor[n/3], {n, 1, 220}]
seqB = Table[n, {n, 1, 220}]; (*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]] (*A187681*)
Complement[Range[Length[seqA]], limseqU] (*A187682*)
(*by Peter J. C. Moses, Mar 12 2011*)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Mar 12 2011
STATUS
approved