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%I #8 Oct 02 2019 08:19:57
%S 1,9,17,33,41,57,65,73,89,97,113,137,145,153,169,177,193,201,209,217,
%T 225,233,257,273,281,289,305,313,329,353,361,385,393,409,417,425,433,
%U 441,449,465,473,489,505,521,529,545,553,569,577,585,601,609,633,641,649,657
%N Numbers k such that k, k+1, ... k+6 are all cubefree (A004709).
%C There cannot be 8 consecutive cubefree numbers since one of them must be divisible by 8 = 2^3.
%C All the terms are congruent to 1 mod 8.
%C The asymptotic density of this sequence is A328017.
%H Amiram Eldar, <a href="/A328016/b328016.txt">Table of n, a(n) for n = 1..10000</a>
%H Leon Mirsky, <a href="https://doi.org/10.1112/plms/s2-50.7.497">Arithmetical pattern problems relating to divisibility by rth powers</a>, Proceedings of the London Mathematical Society, Vol. s2-50, No. 1 (1949), pp. 497-508.
%e 9 is in the sequence since the numbers 9, 10, ... 15 are all cubefree.
%t cubeFreeQ[n_] := FreeQ[FactorInteger[n], {_, k_ /; k > 2}]; aQ[n_] := AllTrue[n + Range[0, 6], cubeFreeQ]; Select[Range[650], aQ]
%Y Cf. A004709, A007675, A194002, A325058, A328017.
%K nonn,easy
%O 1,2
%A _Amiram Eldar_, Oct 01 2019