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 A185302 #15 Aug 20 2023 10:50:50 %S A185302 1,5,7,29,11,131,15,445,214,1315,23,6755,27,15475,5807,62589,35, %T A185302 207302,39,680419,116277,1948963,47,7702195,38936,20726659,2365954, %U A185302 72743987,59,227262211,63,735070461,46142609,2195383507,2123475,7556177030,75,22082968771 %N A185302 a(n) = Sum_{d|n} d*sigma(n/d)^d. %C A185302 Logarithmic derivative of A185301. %F A185302 L.g.f.: Sum_{n>=1} Sum_{k>=1} sigma(n)^k * x^(n*k)/n = Sum_{n>=1} a(n)*x^n/n. %e A185302 L.g.f.: L(x) = x + 5*x^2/2 + 7*x^3/3 + 29*x^4/4 + 11*x^5/5 + 131*x^6/6 + ... where exp(L(x)) = 1 + x + 3*x^2 + 5*x^3 + 14*x^4 + 20*x^5 + 59*x^6 + 83*x^7 + 229*x^8 + 350*x^9 + 878*x^10 + ... + A185301(n)*x^n + ... %t A185302 a[n_] := DivisorSum[n, # * DivisorSigma[1, n/#]^# &]; Array[a, 40] (* _Amiram Eldar_, Aug 18 2023 *) %o A185302 (PARI) {a(n)=sumdiv(n,d,d*sigma(n/d)^d)} %Y A185302 Cf. A000203, A185301. %K A185302 nonn %O A185302 1,2 %A A185302 _Paul D. Hanna_, Jan 25 2012