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%I #12 Nov 05 2017 12:49:26
%S 1,2,3,5,6,7,12,24,100,150,200,300,320,375,500,600,640,700,704,735,
%T 832,960,1014,1088,1200,1815,2023,2400,2535,2940,3549,3610,3840,4046,
%U 4335,4913,5054,5376,5415,5491,6069,6137,6358,6647,7260,7581,7942,8959,9386
%N Numbers n such that sum of digits of n equals the squarefree part of n.
%C The squarefree part of x, core(x), is the smallest integer such that x*core(x) is a square.
%H Giovanni Resta, <a href="/A070274/b070274.txt">Table of n, a(n) for n = 1..10000</a>
%t core[n_]:=Block[{f=FactorInteger[n], p, e}, {p, e} = Transpose[f]; Times@@ (p^Mod[e, 2])]; Select[Range[10^4], core[#] == Plus @@ IntegerDigits[#] &] (* _Giovanni Resta_, Apr 21 2017 *)
%o (PARI) list(lim)=my(v=List()); forfactored(n=1,lim\1, if(core(n)==sumdigits(n[1]), listput(v,n[1]))); Vec(v) \\ _Charles R Greathouse IV_, Nov 05 2017
%Y Cf. A007913, A057531, A057532, A050689, A070275, A063737, A067077, A285494.
%K nonn,base
%O 1,2
%A _Benoit Cloitre_, May 09 2002
%E Data corrected by _Giovanni Resta_, Apr 21 2017
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