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 A283671 #12 Jul 28 2024 03:51:17
%S A283671 2,2,3,2,2,3,2,2,5,3,2,2,2,2,3,2,7,5,2,3,2,2,3,2,2,5,2,2,3,2,2,3,2,2,
%T A283671 7,3,2,2,2,3,2,11,2,5,3,2,2,3,2,2,7,2,5,2,3,2,2,3,2,2,13,3,2,5,2,2,2,
%U A283671 3,2,3,2,3,2,2,2,2,2,2,3,2,2,11,3,2,7
%N A283671 Square root of the single square referenced in A190641.
%H A283671 Robert Price, <a href="/A283671/b283671.txt">Table of n, a(n) for n = 1..10000</a>
%F A283671 a(n) = sqrt(A283670(n)) = A249739(A190641(n)). - _Amiram Eldar_, Jul 28 2024
%e A283671 A190641(4) = 12, 12 = 2*2*3, so 12 has only one square factor, namely 4, and the square root is 2.
%t A283671 f[n_] := Module[{f = FactorInteger[n], ind}, ind = Position[f[[;;, 2]], _?(# > 1 &)]; If[Length[ind] == 1, f[[ind[[1, 1]],1]], Nothing]]; Array[f, 300] (* _Amiram Eldar_, Jul 28 2024 *)
%o A283671 (PARI) lista(kmax) = for(k = 1, kmax, my(f = factor(k)); if(#select(x -> (x>1), f[,2]) == 1, for(i = 1, #f~, if(f[i,2] > 1, print1(f[i,1], ", "); break)))); \\ _Amiram Eldar_, Jul 28 2024
%Y A283671 Cf. A190641, A249739, A283670.
%K A283671 nonn
%O A283671 1,1
%A A283671 _Robert Price_, Mar 13 2017