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A113137 The rational numbers can be ordered by height and then by magnitude (see A002246, A097080); sequence gives denominators. 2
1, 1, 1, 1, 2, 2, 1, 1, 2, 3, 3, 3, 3, 2, 1, 1, 3, 4, 4, 4, 4, 3, 1, 1, 2, 3, 4, 5, 5, 5, 5, 5, 5, 5, 5, 4, 3, 2, 1, 1, 5, 6, 6, 6, 6, 5, 1, 1, 2, 3, 4, 5, 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 6, 5, 4, 3, 2, 1, 1, 3, 5, 7, 8, 8, 8, 8, 8, 8, 8, 8, 7, 5, 3, 1, 1, 2, 4, 5, 7, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

REFERENCES

M. N. Huxley, Area, Lattice Points and Exponential Sums, Oxford, 1996; p. 7.

LINKS

Table of n, a(n) for n=1..105.

Index entries for sequences related to enumerating the rationals

EXAMPLE

The rationals with this ordering, with those of height k in row k (there are 4*A000010(k) rationals of height k, for k>1):

-1 0 1

-2 -1/2 1/2 2

-3 -3/2 -2/3 -1/3 1/3 2/3 3/2 3

-4 -4/3 -3/4 -1/4 1/4 3/4 4/3 4

...

CROSSREFS

Cf. A113136, A002246, A097080.

Sequence in context: A203776 A242357 A120423 * A220603 A238404 A331910

Adjacent sequences:  A113134 A113135 A113136 * A113138 A113139 A113140

KEYWORD

nonn,easy,tabf

AUTHOR

N. J. A. Sloane, Nov 02 2008

EXTENSIONS

More terms from John W. Layman, Nov 06 2008

STATUS

approved

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Last modified December 2 01:23 EST 2020. Contains 338864 sequences. (Running on oeis4.)