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 A360770 #16 Aug 02 2023 01:59:59
%S A360770 1,5,27,260,3125,46684,823543,16777472,387420498,10000003125,
%T A360770 285311670611,8916100495009,302875106592253,11112006826381559,
%U A360770 437893890380860625,18446744073726328848,827240261886336764177,39346408075296925015353
%N A360770 Expansion of Sum_{k>0} (x * (k + x^k))^k.
%F A360770 a(n) = Sum_{d|n} d^(d-n/d+1) * binomial(d,n/d-1).
%F A360770 If p is an odd prime, a(p) = p^p.
%t A360770 a[n_] := DivisorSum[n, #^(# - n/# + 1) * Binomial[#, n/# - 1] &]; Array[a, 20] (* _Amiram Eldar_, Aug 02 2023 *)
%o A360770 (PARI) my(N=20, x='x+O('x^N)); Vec(sum(k=1, N, (x*(k+x^k))^k))
%o A360770 (PARI) a(n) = sumdiv(n, d, d^(d-n/d+1)*binomial(d, n/d-1));
%Y A360770 Cf. A260148, A338693, A360712, A360771.
%Y A360770 Cf. A360774, A360775, A360776.
%K A360770 nonn
%O A360770 1,2
%A A360770 _Seiichi Manyama_, Feb 20 2023