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 A359730 #13 Aug 14 2023 01:59:37
%S A359730 1,5,13,41,81,245,449,1185,2413,5585,11265,26693,53249,118081,248733,
%T A359730 535041,1114113,2390885,4980737,10557201,22050797,46265345,96468993,
%U A359730 201795717,419480401,873123841,1812204685,3760019521,7784628225,16111126325,33285996545,68729044993
%N A359730 a(n) = Sum_{d|n} 2^(d-1) * d^(n/d).
%F A359730 G.f.: Sum_{k>0} k * 2^(k-1) * x^k / (1 - k * x^k).
%t A359730 a[n_] := DivisorSum[n, 2^(#-1) * #^(n/#) &]; Array[a, 32] (* _Amiram Eldar_, Aug 14 2023 *)
%o A359730 (PARI) a(n) = sumdiv(n, d, 2^(d-1)*d^(n/d));
%o A359730 (PARI) my(N=40, x='x+O('x^N)); Vec(sum(k=1, N, k*2^(k-1)*x^k/(1-k*x^k)))
%Y A359730 Cf. A001787, A308366, A359700.
%K A359730 nonn
%O A359730 1,2
%A A359730 _Seiichi Manyama_, Jan 12 2023