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 A188296 #23 Feb 09 2021 02:49:22 %S A188296 846,1682,2890,3626,5048,10926,14750,15850,17406,19942,22022,22023, %T A188296 22626,23274,24649,24650,25774,29350,30250,30925,30926,33174,36702, %U A188296 37250,38726,39446,40474,45374,47674,47675,47726,47826,48374,49490,54586,55026,55449,55450,57122,57123,58474,58850 %N A188296 Central element of a series of 5 successive nonsquarefree numbers. %C A188296 Each of a(n), a(n)-1, a(n)-2, a(n)+1, a(n)+2 has at least one square divisor. %H A188296 Amiram Eldar, <a href="/A188296/b188296.txt">Table of n, a(n) for n = 1..10000</a> %F A188296 a(n) = A078144(n) + 2. - _Amiram Eldar_, Feb 09 2021 %e A188296 846 = 2*3^2*47, 846 - 1 = 5*13^2, 846 - 2 = 2^2*211, 846 + 1 = 7*11^2, 846 + 2 = 2^4*53. %t A188296 Select[Range[1,100000],!SquareFreeQ[#] &&!SquareFreeQ[#-1] &&!SquareFreeQ[#+1] &&!SquareFreeQ[#-2] &&!SquareFreeQ[#+2]&] %Y A188296 Cf. A005117, A013929, A078144. %K A188296 nonn %O A188296 1,1 %A A188296 _Vladimir Joseph Stephan Orlovsky_, Mar 29 2011