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%I #17 Feb 09 2021 02:37:21
%S 1092747,7216618,8870024,8870025,14379271,22635347,24816974,25047846,
%T 33678771,33908368,33908369,34394371,34682346,37923938,49250144,
%U 49250145,53379270,69147868,69147869,70918820,70918821,71927247,72913022,83605071,85972019,90571646
%N Smallest term of a run of at least 8 consecutive integers which are not squarefree.
%H Amiram Eldar, <a href="/A077647/b077647.txt">Table of n, a(n) for n = 1..10000</a>
%F A077647 = { A077640[k] | A077640[k+1] = A077640[k]+1 }. - _M. F. Hasler_, Feb 01 2016
%e n=8870024: squares dividing n+j (j=0...8) i.e. 9 consecutive integers are as follows {4,25,121,841,4,49,961,9,16}
%t s8[x_] := Apply[Plus, Table[Abs[MoebiusMu[x+j]], {j, 0, 7}]] If[Equal[s, 0], Print[n]], {n, 1000000, 100000000}]
%t Flatten[Position[Partition[SquareFreeQ/@Range[91000000],8,1],_?(Union[#]=={False}&),{1},Heads->False]]
%o (PARI) for(n=1,10^8,forstep(k=7,0,-1,issquarefree(n+k)&&(n+=k)&&next(2));print1(n",")) \\ _M. F. Hasler_, Feb 03 2016
%Y Cf. A013929, A051681.
%Y Cf. A045882 (first k-chain), A068781 (2-chains), A070258 (3-chains), A070284 (4-chains), A078144 (5-chains), A049535 (6-chains), A077640 (7-chains), A077647 (8-chains), A078143 (9-chains), A268313 (10-chains), A268314 (11-chains).
%K nonn
%O 1,1
%A _Labos Elemer_, Nov 18 2002
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