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 A070274 #12 Nov 05 2017 12:49:26
%S A070274 1,2,3,5,6,7,12,24,100,150,200,300,320,375,500,600,640,700,704,735,
%T A070274 832,960,1014,1088,1200,1815,2023,2400,2535,2940,3549,3610,3840,4046,
%U A070274 4335,4913,5054,5376,5415,5491,6069,6137,6358,6647,7260,7581,7942,8959,9386
%N A070274 Numbers n such that sum of digits of n equals the squarefree part of n.
%C A070274 The squarefree part of x, core(x), is the smallest integer such that x*core(x) is a square.
%H A070274 Giovanni Resta, <a href="/A070274/b070274.txt">Table of n, a(n) for n = 1..10000</a>
%t A070274 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 A070274 (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 A070274 Cf. A007913, A057531, A057532, A050689, A070275, A063737, A067077, A285494.
%K A070274 nonn,base
%O A070274 1,2
%A A070274 _Benoit Cloitre_, May 09 2002
%E A070274 Data corrected by _Giovanni Resta_, Apr 21 2017