This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A178031 Consider the Farey tree A006842/A006843; a(n) = row at which the denominator n first appears (assumes first row is labeled row 1). 3
 1, 2, 3, 4, 4, 6, 5, 5, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 8, 7, 8, 8, 8, 8, 8, 8, 9, 8, 8, 8, 9, 9, 8, 9, 9, 9, 10, 9, 9, 9, 10, 9, 9, 9, 9, 9, 10, 9, 9, 10, 10, 10, 11, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Computed by Alan Wechsler, Dec 16, 2010. Rich Schroeppel also asked about the analogous sequence giving the last occurrence of denominator n. REFERENCES Based on a posting by Rich Schroeppel to the Math Fun Mailing List, Dec 15 2010. LINKS Bo Gyu Jeong, Table of n, a(n) for n = 1..10000 CROSSREFS See A178047 for another version. Cf. A006842, A006843, A177903, A178042. Sequence in context: A180046 A008329 A064558 * A008328 A091860 A181833 Adjacent sequences:  A178028 A178029 A178030 * A178032 A178033 A178034 KEYWORD nonn,more AUTHOR N. J. A. Sloane, Dec 16 2010 EXTENSIONS More terms from Bo Gyu Jeong, Oct 20 2012 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .