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 A348349 #12 Oct 15 2021 08:38:24
%S A348349 1,3,4,19,6,222,8,531,85,1008,12,249070,14,2754,3384,66067,18,1889871,
%T A348349 20,3201024,9272,10662,24,4586721006,631,17592,19768,17213138,30,
%U A348349 21870004602,32,33620499,35952,39324,42888,2821112046175,38,54894,59336,163843201536
%N A348349 a(n) = Sum_{d|n} d^(tau(d) - 1).
%F A348349 G.f.: Sum_{k>=1} k^(tau(k) - 1) * x^k/(1 - x^k).
%F A348349 If p is prime, a(p) = 1 + p.
%t A348349 a[n_] := DivisorSum[n, #^(DivisorSigma[0, #] - 1) &]; Array[a, 40] (* _Amiram Eldar_, Oct 14 2021 *)
%o A348349 (PARI) a(n) = sumdiv(n, d, d^(numdiv(d)-1));
%o A348349 (PARI) my(N=66, x='x+O('x^N)); Vec(sum(k=1, N, k^(numdiv(k)-1)*x^k/(1-x^k)))
%Y A348349 Cf. A000005 (tau), A174937, A347405, A347992, A348350.
%K A348349 nonn
%O A348349 1,2
%A A348349 _Seiichi Manyama_, Oct 14 2021