A113137 The rational numbers can be ordered by height and then by magnitude (see A002246, A097080); sequence gives denominators.

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

Offset: 1

Author

N. J. A. Sloane, Nov 02 2008

Keywords

• nonn
• easy
• tabf

Examples

			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
...
		

References

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

Links

• Index entries for sequences related to enumerating the rationals

Crossrefs

Cf. A113136, A002246, A097080.

Extensions

More terms from John W. Layman, Nov 06 2008