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%I #7 Sep 11 2019 04:51:21
%S 1,4,6,15,18,48,66,154,267,552,1026,2154,4098,8328,16428,33061,65538,
%T 131676,262146,525390,1048716,2099208,4194306,8393124,16777251,
%U 33562632,67109392,134234334,268435458,536904864,1073741826,2147549616
%N Dirichlet convolution of d(n) (# of divisors) with b_n=2^(n-1).
%F a(n) ~ 2^(n-1). - _Vaclav Kotesovec_, Sep 11 2019
%t Table[Sum[DivisorSigma[0, n/d]*2^(d - 1), {d, Divisors[n]}], {n, 1, 30}] (* _Vaclav Kotesovec_, Sep 10 2019 *)
%K nonn
%O 1,2
%A _Erich Friedman_