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 A368474 #7 Dec 27 2023 01:19:55
%S A368474 1,1,1,1,1,1,1,1,1,1,1,4,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,4,1,
%T A368474 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,4,4,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
%U A368474 1,1,1,1,1,1,4,1,1,1,1,1,1,1,1,1,1,1,1
%N A368474 Product of exponents of prime factorization of the numbers whose exponents in their prime power factorization are squares (A197680).
%C A368474 All the terms are squares (A000290).
%C A368474 The first position of k^2, for k = 1, 2, ..., is 1, 12, 331, 834, 21512290, 26588, ..., which is the position of A085629(k^2) in A197680.
%H A368474 Amiram Eldar, <a href="/A368474/b368474.txt">Table of n, a(n) for n = 1..10000</a>
%F A368474 a(n) = A005361(A197680(n)).
%F A368474 Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = (1/d) * Product_{p prime} (1 + Sum_{k>=1} k^2/p^(k^2)) = 1.16776748073813763932..., where d = A357016 is the asymptotic density of A197680.
%t A368474 f[n_] := Module[{e = FactorInteger[n][[;; , 2]]}, If[AllTrue[e, IntegerQ[Sqrt[#]] &], Times @@ e, Nothing]]; Array[f, 150]
%o A368474 (PARI) lista(kmax) = {my(e, ok); for(k = 1, kmax, e = factor(k)[, 2]; ok = 1; for(i = 1, #e, if(!issquare(e[i]), ok = 0; break)); if(ok, print1(vecprod(e), ", ")));}
%Y A368474 Cf. A000290, A005361, A085629, A197680, A357016.
%Y A368474 Similar sequences: A322327, A368472, A368473.
%K A368474 nonn,easy
%O A368474 1,12
%A A368474 _Amiram Eldar_, Dec 26 2023