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 A342617 #16 Mar 18 2021 08:25:00
%S A342617 1,2,3,4,5,20,7,38,135,4102,11,1670,13,1679624,4202505,270346,17,
%T A342617 60539912,19,4299292682,470185508877,1000000000012,23,17253793802,
%U A342617 4398046511125,1283918464548878,609359773564947,131622174060806158,29,4789472952582154,31
%N A342617 a(n) = Sum_{d|n} phi(d)^(n-d+1).
%H A342617 Seiichi Manyama, <a href="/A342617/b342617.txt">Table of n, a(n) for n = 1..605</a>
%F A342617 a(n) = Sum_{k=1..n} phi(n/gcd(k,n))^(n - n/gcd(k,n)).
%F A342617 G.f.: Sum_{k>=1} phi(k) * x^k/(1 - (phi(k) * x)^k).
%F A342617 If p is prime, a(p) = p.
%t A342617 a[n_] := DivisorSum[n, EulerPhi[#]^(n - # + 1) &]; Array[a, 30] (* _Amiram Eldar_, Mar 17 2021 *)
%o A342617 (PARI) a(n) = sumdiv(n, d, eulerphi(d)^(n-d+1));
%o A342617 (PARI) a(n) = sum(k=1, n, eulerphi(n/gcd(k, n))^(n-n/gcd(k, n)));
%o A342617 (PARI) my(N=40, x='x+O('x^N)); Vec(sum(k=1, N, eulerphi(k)*x^k/(1-(eulerphi(k)*x)^k)))
%Y A342617 Cf. A000010, A342607.
%K A342617 nonn
%O A342617 1,2
%A A342617 _Seiichi Manyama_, Mar 16 2021