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 A073248 #12 Mar 03 2022 01:44:45
%S A073248 10,46,61,73,82,118,122,133,145,154,173,190,205,226,246,262,273,277,
%T A073248 290,298,313,326,334,370,373,385,406,421,426,442,457,473,478,493,505,
%U A073248 514,526,537,565,573,586,601,606,622,626,658,673,694,709,730,733,745
%N A073248 Squarefree numbers k such that k+1 is also squarefree, but k-1 and k+2 are not.
%H A073248 Robert Israel, <a href="/A073248/b073248.txt">Table of n, a(n) for n = 1..10000</a>
%p A073248 state:= [true,true,true,true]:
%p A073248 R:= NULL: count:= 0:
%p A073248 for n from 1 while count < 100 do
%p A073248 state:= [state[2],state[3],state[4],numtheory:-issqrfree(n)];
%p A073248 if state = [false,true,true,false] then
%p A073248 R:= R, n-2; count:= count+1
%p A073248 fi
%p A073248 od:
%p A073248 R; # _Robert Israel_, Mar 02 2022
%t A073248 Transpose[SequencePosition[Table[If[SquareFreeQ[n],1,0],{n,800}],{0,1,1,0}]][[1]]+1 (* The program uses the SequencePosition function from Mathematica version 10 *) (* _Harvey P. Dale_, Mar 09 2016 *)
%Y A073248 Cf. A005117, A073250, A073247, A007675.
%K A073248 nonn
%O A073248 1,1
%A A073248 _Reinhard Zumkeller_, Jul 22 2002