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 A359485 #21 May 10 2023 04:31:04
%S A359485 1,-5,-9,4,-25,45,-49,0,0,125,-121,-36,-169,245,225,0,-289,0,-361,
%T A359485 -100,441,605,-529,0,0,845,0,-196,-841,-1125,-961,0,1089,1445,1225,0,
%U A359485 -1369,1805,1521,0,-1681,-2205,-1849,-484,0,2645,-2209,0,0,0,2601,-676,-2809,0,3025,0,3249,4205,-3481,900,-3721,4805,0
%N A359485 a(1) = 1, a(2) = -5; a(n) = -n^2 * Sum_{d|n, d < n} a(d) / d^2.
%H A359485 Seiichi Manyama, <a href="/A359485/b359485.txt">Table of n, a(n) for n = 1..10000</a>
%F A359485 a(n) is multiplicative with a(2)= -5, a(4)= 4, a(2^e)= 0 if e>2. a(p)= -p^2, a(p^e)= 0 if e>1, p>2.
%F A359485 G.f. A(x) satisfies x * (1 - x) = Sum_{k>=1} k^2 * A(x^k).
%t A359485 f[p_, e_] := If[e == 1, -p^2, 0]; f[2, e_] := Switch[e, 1, -5, 2, 4, _, 0]; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* _Amiram Eldar_, May 10 2023 *)
%Y A359485 Partial sums give A360390.
%Y A359485 Cf. A092673, A359484, A359531.
%Y A359485 Cf. A334657.
%K A359485 sign,mult
%O A359485 1,2
%A A359485 _Seiichi Manyama_, Apr 01 2023