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A329231
The maximum number of times one reaches a single position during the grasshopper procedure.
4
1, 1, 1, 1, 3, 2, 1, 1, 4, 3, 3, 3, 3, 3, 3, 1, 5, 2, 3, 3, 4, 3, 5, 3, 3, 4, 5, 3, 4, 4, 4, 1, 4, 4, 3, 4, 4, 3, 3, 5, 4, 5, 3, 3, 4, 4, 5, 4, 6, 4, 5, 4, 5, 4, 5, 4, 4, 4, 5, 5, 4, 5, 5, 1, 4, 4, 5, 3, 4, 5, 5, 4, 4, 7, 4, 4, 4, 5, 5, 5, 4, 4, 4, 4, 4, 5, 4
OFFSET
1,5
COMMENTS
The grasshopper procedure: n positions are evenly spaced around a circle, a grasshopper hops randomly to any position, after the k-th hop, the grasshopper looks clockwise and counterclockwise k positions. If one of the positions has been visited less often then the other, it hops there; if both positions have been visited an equal number of times, it hops k steps in the clockwise position. (See Mathematics Stack Exchange link for more details.)
a(n) >= (A329230(n)-1)/(n-1).
Least values of n such that a(n) = 1, 2, 3, etc are 1, 6, 5, 9, 17, 49, 74, 198, 688, 1745 etc.
Conjecture: a(n) = 1 if and only if n = 3, n = 7, or n = 2^k for some k.
Conjecture: The largest values of n for which a(n) = 2, 3, 4, 5 respectively are n = 18, 68, 381, 1972.
If the second conjecture is true, then 2, 3, 4, and 5 appear 2, 19, 87, and 313 times respectively.
Conjecture: Every integer greater than 1 appears in this sequence a finite number of times.
LINKS
Mathematics Stack Exchange User Vepir, Grasshopper jumping on circles
CROSSREFS
KEYWORD
nonn,walk
AUTHOR
Peter Kagey, Nov 08 2019
STATUS
approved