

A157807


Numerators of fractions arranged in Cantor's ordering (1/1, 2/1, 1/2, 1/3, 3/1, 4/1, 3/2, 2/3, 1/4, 1/5, 5/1, 6/1, 5/2, ...) with equivalent fractions removed.


4



1, 2, 1, 1, 3, 4, 3, 2, 1, 1, 5, 6, 5, 4, 3, 2, 1, 1, 3, 5, 7, 8, 7, 5, 4, 2, 1, 1, 3, 7, 9, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 1, 5, 7, 11, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 1, 3, 5, 9, 11, 13, 14, 13, 11, 8, 7, 4, 2, 1, 1, 3, 5, 7, 9, 11, 13, 15, 16, 15, 14
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OFFSET

1,2


LINKS

Table of n, a(n) for n=1..82.


PROG

(Python)
from fractions import gcd
for s in range(2, 100, 2):
..for i in range(1, s):
....if gcd(i, s  i) != 1: continue
....print(i)
..for i in range(s, 0, 1):
....if gcd(i, s + 1  i) != 1: continue
....print(i)
# Hiroaki Yamanouchi, Oct 06 2014


CROSSREFS

Cf. A157813, denominators of the same sequence of fractions. Cf. A038566.
Sequence in context: A237498 A319516 A015138 * A100529 A262953 A226209
Adjacent sequences: A157804 A157805 A157806 * A157808 A157809 A157810


KEYWORD

nonn,frac


AUTHOR

Ron R. King, Mar 07 2009


EXTENSIONS

Anumber in crossreference corrected by R. J. Mathar, Sep 23 2009
a(19)a(20) corrected and a(58)a(82) added by Hiroaki Yamanouchi, Oct 06 2014


STATUS

approved



