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