This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A077647 #20 Jun 22 2025 21:31:36
%S A077647 1092747,7216618,8870024,8870025,14379271,22635347,24816974,25047846,
%T A077647 33678771,33908368,33908369,34394371,34682346,37923938,49250144,
%U A077647 49250145,53379270,69147868,69147869,70918820,70918821,71927247,72913022,83605071,85972019,90571646
%N A077647 Smallest term of a run of at least 8 consecutive integers which are not squarefree.
%H A077647 Amiram Eldar, <a href="/A077647/b077647.txt">Table of n, a(n) for n = 1..10000</a>
%F A077647 A077647 = { A077640[k] | A077640[k+1] = A077640[k]+1 }. - _M. F. Hasler_, Feb 01 2016
%e A077647 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 A077647 s8[x_] := Apply[Plus, Table[Abs[MoebiusMu[x+j]], {j, 0, 7}]]; Do[If[s8[n] == 0, Print[n]], {n, 10^8}]
%t A077647 Flatten[Position[Partition[SquareFreeQ/@Range[91000000],8,1],_?(Union[#]=={False}&),{1},Heads->False]]
%o A077647 (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 A077647 Cf. A013929, A051681.
%Y A077647 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 A077647 nonn
%O A077647 1,1
%A A077647 _Labos Elemer_, Nov 18 2002