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%I #11 Mar 31 2019 02:39:31
%S 2,9,14,27,34,53,64,89,102,133,150,187,206,249,272,321,346,401,430,
%T 491,522,589,624,697,734,813,854,939,982,1073,1120,1217,1266,1369,
%U 1422,1531,1586,1701,1760,1881,1942,2069,2134,2267,2334,2473
%N Numbers k for which A324274(k) is 0, i.e., starting squares in A324274 that yield a path of infinite length.
%C Note that the sequence up to a(n) (for its current known values) is actually the path of a(n) in reverse until it reaches square 2. It is therefore conjectured that all starting squares in A324274 either have a finite length or are part of this single sequence.
%F Conjectures from _Colin Barker_, Mar 09 2019: (Start)
%F G.f.: x*(2 + 7*x + 3*x^2 + 6*x^3 - x^5 + x^6) / ((1 - x)^3*(1 + x)^2*(1 + x^2)).
%F a(n) = (5 + 7*(-1)^n + (2-2*i)*(-i)^n + (2+2*i)*i^n + (26+6*(-1)^n)*n + 18*n^2) / 16 where i=sqrt(-1).
%F a(n) = a(n-1) + a(n-2) - a(n-3) + a(n-4) - a(n-5) - a(n-6) + a(n-7) for n>7.
%F (End)
%Y Cf. A316588, A324273, A324274.
%K nonn
%O 1,1
%A _Jan Koornstra_, Feb 27 2019
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