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 A071327 #30 May 15 2025 00:50:11
%S A071327 0,0,0,4,0,0,0,4,9,0,0,4,0,0,0,4,0,9,0,4,0,0,0,4,25,0,9,4,0,0,0,4,0,0,
%T A071327 0,13,0,0,0,4,0,0,0,4,9,0,0,4,49,25,0,4,0,9,0,4,0,0,0,4,0,0,9,4,0,0,0,
%U A071327 4,0,0,0,13,0,0,25,4,0,0,0,4,9,0,0,4,0,0,0,4,0,9,0
%N A071327 Sum of the squared primes dividing n.
%H A071327 Antti Karttunen, <a href="/A071327/b071327.txt">Table of n, a(n) for n = 1..65537</a>
%F A071327 a(n) = Sum_{d|n} A010052(d)*A010051(A000196(d))*d. - _Antti Karttunen_, Nov 18 2017
%F A071327 G.f.: Sum_{k>=1} prime(k)^2 * x^(prime(k)^2) / (1 - x^(prime(k)^2)). - _Ilya Gutkovskiy_, Apr 06 2020
%F A071327 a(n) = Sum_{p^2|n} p^2. - _Wesley Ivan Hurt_, Feb 21 2022
%F A071327 Additive with a(p^e) = p^2 if e >= 2, and 0 otherwise. - _Amiram Eldar_, May 15 2025
%t A071327 Array[DivisorSum[#, # &, PrimeQ@ Sqrt@ # &] &, 91] (* _Michael De Vlieger_, Nov 18 2017 *)
%o A071327 (PARI) A071327(n) = { my(r); sumdiv(n,d,(issquare(d,&r)&&isprime(r)) * d); } \\ _Antti Karttunen_, Nov 19 2017
%Y A071327 Cf. A000196, A010051, A010052, A056170, A063958, A071326.
%K A071327 nonn
%O A071327 1,4
%A A071327 _Reinhard Zumkeller_, May 18 2002