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 A333824 #16 Jul 09 2023 12:13:29
%S A333824 1,1,4,1,6,10,8,1,37,26,12,82,14,50,384,1,18,811,20,626,2552,122,24,
%T A333824 6562,3151,170,20440,2402,30,74900,32,1,178512,290,94968,538003,38,
%U A333824 362,1596560,390626,42,4901060,44,14642,16364502,530,48,43046722,823593,9766251
%N A333824 a(n) = Sum_{d|n, n/d odd} (n/d)^d.
%H A333824 Seiichi Manyama, <a href="/A333824/b333824.txt">Table of n, a(n) for n = 1..5000</a>
%F A333824 G.f.: Sum_{k>=1} (2*k - 1) * x^(2*k - 1) / (1 - (2*k - 1)*x^(2*k - 1)).
%F A333824 a(2^n) = 1. - _Seiichi Manyama_, Apr 07 2020
%F A333824 a(n) = Sum_{d|n, d odd} d^(n/d). - _Chai Wah Wu_, Jul 09 2023
%t A333824 Table[DivisorSum[n, (n/#)^# &, OddQ[n/#] &], {n, 50}]
%t A333824 nmax = 50; CoefficientList[Series[Sum[(2 k - 1) x^(2 k - 1)/(1 - (2 k - 1) x^(2 k - 1)), {k, 1,nmax}], {x, 0, nmax}], x] // Rest
%o A333824 (PARI) a(n) = sumdiv(n, d, if ((n/d)%2, (n/d)^d)); \\ _Michel Marcus_, Apr 07 2020
%o A333824 (Python)
%o A333824 from sympy import divisors
%o A333824 def A333824(n): return sum(d**(n//d) for d in divisors(n>>(~n & n-1).bit_length(),generator=True)) # _Chai Wah Wu_, Jul 09 2023
%Y A333824 Cf. A055225, A333823.
%K A333824 nonn
%O A333824 1,3
%A A333824 _Ilya Gutkovskiy_, Apr 06 2020