|
Search: id:A081482
|
|
|
| A081482 |
|
Consider the mapping f(a/b) = (a^3 +b^3)/(a^2+b^2). Taking a =1, b = 2 to start with, and carrying out this mapping repeatedly on each new (reduced) rational number gives the following sequence 1/2,9/5,427/53,39001680/92569,... Sequence contains the denominators. |
|
+0
2
|
|
| 2, 5, 53, 92569, 1521139611842161, 1759826706496123129893760473796973076447567001, 5450165776683729363553774731808009059782198745252457060273092560160498157854877231868041524958184901475157837190479609639387791150077013
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
The mapping f(a/b) = (a + b)/(a - b). Taking a = 2 b = 1 to start with, and carrying out this mapping repeatedly on each new (reduced)rational number gives the periodic sequence 2/1,3/1,2/1,3/1,...
|
|
CROSSREFS
|
Cf. A081481.
Sequence in context: A081090 A071880 A071882 this_sequence A134475 A114029 A013171
Adjacent sequences: A081479 A081480 A081481 this_sequence A081483 A081484 A081485
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Mar 24 2003
|
|
EXTENSIONS
|
More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003
|
|
|
Search completed in 0.002 seconds
|
