|
| |
|
|
A137417
|
|
Limiting sequence when we start with positive integers (A000027) and at step n >= 1 add to the term at position n + a(n) the value a(n).
|
|
12
|
|
|
|
1, 3, 3, 4, 8, 9, 7, 12, 9, 10, 11, 12, 21, 21, 24, 16, 17, 27, 19, 42, 21, 33, 23, 36, 25, 26, 27, 28, 29, 30, 31, 48, 33, 72, 56, 36, 37, 57, 63, 40, 41, 63, 43, 44, 72, 69, 47, 48, 49, 75, 51, 78, 53, 81, 88, 84, 57, 87, 59, 126, 61, 135, 63, 64, 65, 99, 67, 68, 69, 70, 71
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
COMMENTS
|
At the vast majority of positions the term is changed at most once, but at some positions a change occurs twice. An example is position 20. In step 4 the term at position 4 + a(4) = 8 is changed to 8 + a(4) = 12; in step 8 the term at position 8 + a(8) = 20 is changed to 20 + a(8) = 32; in step 10 the term at position 10 + a(10) = 20 is changed to a(20) + a(10) = 32 + 10 = 42.
The first position where the term is changed three times is 3498. [Klaus Brockhaus, Apr 23 2008]
The first position where the term is changed four times is 1024914. [Rémy Sigrist, Mar 11 2017]
|
|
|
LINKS
|
Rémy Sigrist, Table of n, a(n) for n = 1..10000
Rémy Sigrist, Scatterplot of first 2000000 terms
|
|
|
MAPLE
|
P:=proc(i) local a, n, v; v:=array(1..i); for n from 1 by 1 to i do v[n]:=n; od; for n from 1 by 1 to 200 do v[v[n]+n]:=v[v[n]+n]+v[n]; od; for n from 1 by 1 to 200 do print(v[n]); od; end: P(1000); # Paolo P. Lava, Mar 10 2009
|
|
|
CROSSREFS
|
Cf. A000027.
Sequence in context: A340429 A147679 A339054 * A137418 A285445 A327745
Adjacent sequences: A137414 A137415 A137416 * A137418 A137419 A137420
|
|
|
KEYWORD
|
easy,nonn
|
|
|
AUTHOR
|
Ctibor O. Zizka, Apr 16 2008
|
|
|
EXTENSIONS
|
Extended by Klaus Brockhaus, Apr 23 2008
|
|
|
STATUS
|
approved
|
| |
|
|
