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A189533
n+[ns/r]+[nt/r]; r=1, s=arcsin(3/5), t=arcsin(4/5).
3
1, 4, 6, 9, 12, 14, 17, 20, 22, 25, 28, 30, 33, 35, 37, 40, 42, 45, 48, 50, 53, 56, 58, 61, 64, 66, 69, 71, 73, 76, 78, 81, 84, 86, 89, 92, 94, 97, 100, 102, 105, 107, 109, 112, 114, 117, 120, 122, 125, 128, 130, 133, 136, 138, 141, 143, 145, 148, 150, 153, 156, 158, 161, 164, 166, 169, 172, 174, 176, 179, 181, 184, 186, 189, 192, 194, 197, 200, 202, 205, 208, 210, 212, 215
OFFSET
1,2
COMMENTS
This is one of three sequences that partition the positive integers. In general, suppose that r, s, t are positive real numbers for which the sets {i/r: i>=1}, {j/s: j>=1}, {k/t: k>=1} are pairwise disjoint. Let a(n) be the rank of n/r when all the numbers in the three sets are jointly ranked. Define b(n) and c(n) as the ranks of n/s and n/t. It is easy to prove that
a(n)=n+[ns/r]+[nt/r],
b(n)=n+[nr/s]+[nt/s],
c(n)=n+[nr/t]+[ns/t], where []=floor.
Taking r=1, s=arcsin(3/5), t=arcsin(4/5) gives
MATHEMATICA
r=1; s=ArcSin[3/5]; t=ArcSin[4/5];
a[n_] := n + Floor[n*s/r] + Floor[n*t/r];
b[n_] := n + Floor[n*r/s] + Floor[n*t/s];
c[n_] := n + Floor[n*r/t] + Floor[n*s/t];
Table[a[n], {n, 1, 120}] (*A189533*)
Table[b[n], {n, 1, 120}] (*A189534*)
Table[c[n], {n, 1, 120}] (*A189535*)
CROSSREFS
Sequence in context: A066095 A003622 A330215 * A047408 A060644 A122550
KEYWORD
nonn
AUTHOR
Clark Kimberling, Apr 23 2011
EXTENSIONS
a(84) corrected by Georg Fischer, Jun 10 2020
STATUS
approved