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%I #10 May 07 2021 00:54:37
%S 1,2,4,8,19,58,209,888,4150,21170,115985,678642,4213609,27644652,
%T 190899368,1382959444,10480142163,82864874064,682076806177,
%U 5832742226266,51724158235802,474869816272746,4506715738447345
%N Dirichlet convolution of phi(n) with Bell numbers.
%F From _Richard L. Ollerton_, May 06 2021: (Start)
%F a(n) = Sum_{d|n} phi(d)*A000110(n/d) (by definition).
%F a(n) = Sum_{k=1..n} A000110(gcd(n,k)).
%F a(n) = Sum_{k=1..n} A000110(n/gcd(n,k))*phi(gcd(n,k))/phi(n/gcd(n,k)). (End)
%t Table[Sum[BellB[n/d - 1]*EulerPhi[d], {d, Divisors[n]}], {n, 1, 25}] (* _Vaclav Kotesovec_, Sep 10 2019 *)
%Y Cf. A000010, A000110
%K nonn
%O 1,2
%A _Erich Friedman_
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