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A187841
Rank transform of the sequence floor(n*sqrt(2)+1/2); complement of A187842.
2
1, 3, 5, 7, 8, 10, 12, 14, 16, 17, 19, 21, 23, 25, 26, 28, 30, 31, 34, 35, 37, 39, 41, 42, 44, 46, 48, 50, 51, 53, 55, 57, 59, 60, 62, 64, 66, 68, 69, 71, 73, 74, 77, 78, 80, 82, 83, 85, 87, 89, 91, 93, 95, 96, 98, 100, 102, 103, 105, 107, 109, 111, 112, 114, 116, 117, 119, 121, 123, 125, 126, 128, 130, 132, 134, 135, 137, 139, 141, 143, 145, 146
OFFSET
1,2
COMMENTS
See A187224.
MATHEMATICA
r=2^(1/2);
seqA = Table[Floor[r*n+1/2], {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]] (*A187841*)
Complement[Range[Length[seqA]], limseqU] (*A187842*)
(*by Peter J. C. Moses, Mar 13 2011*)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Mar 13 2011
STATUS
approved