A187681 Rank transform of the sequence floor(n/3); complement of A187682.

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.

Links

Table of n, a(n) for n=1..97.

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

Cf. A187224, A187682, A187683, A187685, A187687.

Sequence in context: A359913 A247915 A284676 * A107750 A196736 A284946

Adjacent sequences: A187678 A187679 A187680 * A187682 A187683 A187684

Keyword

nonn

Author

Clark Kimberling, Mar 12 2011

Status

approved