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%I #19 Oct 24 2016 02:57:47
%S 1,1,1,11,1,33,5,83,9,217,13,99,17,233,21,1159,17,313,33,95,21,117,37,
%T 249,25,731,33,4729,21,107,69,447,41,5869,53,345,53,2949,109,3437,217,
%U 359,73,769,57,10181,81,2291,97,3217,73,6445,105,493,81,6035,113
%N Intervals between iterations at which Langton's Ant living on triangular tiling reaches the distance of n from the origin for the first time.
%C 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]
%H Andrey Zabolotskiy, <a href="/A275304/b275304.txt">Table of n, a(n) for n = 1..1500</a> (calculated using _Oleg Nikulin_'s program)
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Turmite">Turmite</a>
%F a(n) = A275303(n) - A275303(n-1).
%Y Cf. A269757, A275302, A275303 (cumulative sums), A275305.
%K nonn
%O 1,4
%A _Oleg Nikulin_, Jul 22 2016