|
Search: id:A057690
|
|
|
| A057690 |
|
Length of cycle in trajectory of P under the `Px+1' map, where P = n-th prime, or -1 if trajectory does not cycle. |
|
+0
8
|
|
| 3, 3, 4, 4, 3, 4, 4, 5, 4, 6, 3, 4, 4, 6, 5, 5, 3, 4, 6, 3, 6, 5, 5, 4, 4, 5, 6, 4, 4, 8, 5, 4, 5, 5, 5, 3, 4, 6, 4, 6, 4, 8, 3, 5, 6, 4, 7, 5, 4, 5, 7, 4, 6, 4, 6, 6, 6, 3, 12, 4, 5, 5, 6, 3, 4, 4, 4, 5, 5, 4, 7, 6, 4, 5, 9, 5, 3, 4, 4, 6, 3, 8, 4, 6, 5, 6, 3, 5, 6, 6, 8, 5, 5, 6, 7, 5, 5, 4, 3, 4, 5, 5, 5, 5, 4
(list; graph; listen)
|
|
|
OFFSET
|
2,1
|
|
|
COMMENT
|
See A057684 for definition.
Note that not all cycles for the iteration starting with p contain the number 1; a(60), for the prime 281, is the first example of this. Its iterates are: 281, 78962, 39481, 3037, 853398, 426699, 142233, 47411, 6773, 521, 146402, 73201, 1031, 289712, 144856, 72428, 36214, 18107, 953, 267794, 133897, with the last 12 terms cycling. Another example is provided by 2543, the 372nd prime. - T. D. Noe, Apr 02 2008
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=2..1000
|
|
EXAMPLE
|
For n=3, P=7: trajectory of 7 is 7, 50, 25, 5, 1, 8, 4, 2, 1, 8, 4, 2, 1, 8, 4, 2, 1, ..., which has maximal term 50, cycle length 4 and there are 4 terms before it enters the cycle.
|
|
CROSSREFS
|
Cf. A057446, A057216, A057522, A057534, A057614. See also A033478, A057688, A057684, A057685, A057686, A057687, A057689, A057691.
Sequence in context: A062069 A027011 A061023 this_sequence A090972 A136546 A058729
Adjacent sequences: A057687 A057688 A057689 this_sequence A057691 A057692 A057693
|
|
KEYWORD
|
nonn,nice,easy
|
|
AUTHOR
|
njas, Oct 20 2000
|
|
EXTENSIONS
|
More terms from Larry Reeves (larryr(AT)acm.org), Nov 08 2000
Corrected by T. D. Noe, Apr 02 2008
|
|
|
Search completed in 0.002 seconds
|
