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A275304
Intervals between iterations at which Langton's Ant living on triangular tiling reaches the distance of n from the origin for the first time.
4
1, 1, 1, 11, 1, 33, 5, 83, 9, 217, 13, 99, 17, 233, 21, 1159, 17, 313, 33, 95, 21, 117, 37, 249, 25, 731, 33, 4729, 21, 107, 69, 447, 41, 5869, 53, 345, 53, 2949, 109, 3437, 217, 359, 73, 769, 57, 10181, 81, 2291, 97, 3217, 73, 6445, 105, 493, 81, 6035, 113
OFFSET
1,4
COMMENTS
The distance is defined as the number of steps needed to reach the origin (analog of Manhattan distance). It seems that starting from n=625 (which corresponds to iterations around 26,000,000), a(n)=53 for odd n. [amended by Andrey Zabolotskiy, Oct 09 2016]
LINKS
Andrey Zabolotskiy, Table of n, a(n) for n = 1..1500 (calculated using Oleg Nikulin's program)
Wikipedia, Turmite
FORMULA
a(n) = A275303(n) - A275303(n-1).
CROSSREFS
Cf. A269757, A275302, A275303 (cumulative sums), A275305.
Sequence in context: A174221 A194039 A298084 * A245677 A182041 A086994
KEYWORD
nonn
AUTHOR
Oleg Nikulin, Jul 22 2016
STATUS
approved