%I #15 Aug 07 2022 12:30:17
%S 1,5,23,146,874,8124,62628,707664,7860816,103284000,1179669600,
%T 24454569600,324615427200,5740203974400,119579523436800,
%U 2688723275212800,46084905896601600,1383333631684300800,26411386476116275200,868104140064602112000
%N a(n) = n! * Sum_{k=1..n} ( Sum_{d|k} d^(k/d) )/k.
%H Vaclav Kotesovec, <a href="/A356436/a356436.jpg">Graph - the asymptotic ratio (10000 terms)</a>
%F a(n) = n! * Sum_{k=1..n} A055225(k)/k.
%F E.g.f.: -(1/(1-x)) * Sum_{k>0} log(1 - k*x^k)/k.
%F a(n) ~ (n-1)! * 3^((n + 3 - mod(n,3))/3)/2. - _Vaclav Kotesovec_, Aug 07 2022
%o (PARI) a(n) = n!*sum(k=1, n, sumdiv(k, d, d^(k/d))/k);
%o (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(-sum(k=1, N, log(1-k*x^k)/k)/(1-x)))
%Y Cf. A055225, A353992, A356297, A356437, A356439.
%K nonn
%O 1,2
%A _Seiichi Manyama_, Aug 07 2022
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