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%I #16 Aug 27 2023 17:03:11
%S 1,26,21953,5554571867,298500366308609377,
%T 11413459460309090640625021978,
%U 256925761343390078522337875137209684721665,6476754651706496208416137876625690606552226172163824554588
%N a(n) = Sum_{d|n} sigma_d(d)^d.
%H Seiichi Manyama, <a href="/A359054/b359054.txt">Table of n, a(n) for n = 1..26</a>
%F G.f.: Sum_{k >= 1} (sigma_k(k) * x)^k/(1 - x^k).
%t a[n_] := DivisorSum[n, DivisorSigma[#, #]^# &]; Array[a, 8] (* _Amiram Eldar_, Aug 27 2023 *)
%o (PARI) a(n) = sumdiv(n, d, sigma(d, d)^d);
%o (PARI) my(N=10, x='x+O('x^N)); Vec(sum(k=1, N, (sigma(k, k)*x)^k/(1-x^k)))
%Y Cf. A344047, A359052, A359053.
%K nonn
%O 1,2
%A _Seiichi Manyama_, Dec 14 2022
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