|
|
A085059
|
|
a(1) = 1, a(n+1) = a(n)-n if a(n) > n else a(n+1) = a(n) + n.
|
|
5
|
|
|
1, 2, 4, 1, 5, 10, 4, 11, 3, 12, 2, 13, 1, 14, 28, 13, 29, 12, 30, 11, 31, 10, 32, 9, 33, 8, 34, 7, 35, 6, 36, 5, 37, 4, 38, 3, 39, 2, 40, 1, 41, 82, 40, 83, 39, 84, 38, 85, 37, 86, 36, 87, 35, 88, 34, 89, 33, 90, 32, 91, 31, 92, 30, 93, 29, 94, 28, 95, 27, 96, 26, 97, 25, 98, 24, 99
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
Let (3^k-1)/2 = r then a((3^k-1)/2) = a(r) = 1 and a(r-1) = r. Geometrical interpretation. The sequence is obtained by the following rule: A point moves on the positive number line with the rule that in every step it has to move one unit more than the previous step and with the aim that it is to be as close to 0 as possible but on the positive side.
|
|
LINKS
|
|
|
MATHEMATICA
|
RecurrenceTable[{a[1]==1, a[n+1]==If[a[n]>n, a[n]-n , a[n]+n]}, a[n], {n, 80}] (* Harvey P. Dale, May 11 2011 *)
|
|
PROG
|
(Haskell)
a085059 n = a085059_list !! (n-1)
a085059_list = 1 : f 1 1 where
f v w = y : f (v + 1) y where
y = if w > v then w - v else w + v
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 27 2003
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|