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%I #8 Aug 20 2023 10:50:29
%S 2,34,1538,262178,167772162,412316861986,3940649673949186,
%T 147573952589676675106,21760664753063325144712706,
%U 12676506002282294014967199825954,29243015907268149203883755326167580674,267608942382367477698428619271780750388889122
%N a(n) = Sum_{d|n} d*2^(d^2).
%e L.g.f.: L(x) = 2*x + 34*x^2/2 + 1538*x^3/3 + 262178*x^4/4 + ...
%e exp(L(x)) = 1 + 2*x + 19*x^2 + 548*x^3 + 66749*x^4 + ... (A158099).
%t a[n_] := DivisorSum[n, # * 2^(#^2) &]; Array[a, 10] (* _Amiram Eldar_, Aug 18 2023 *)
%o (PARI) a(n)=sumdiv(n, d, d*2^(d^2))
%Y Cf. A158099.
%K nonn
%O 1,1
%A _Paul D. Hanna_, Dec 16 2009
%E a(11)-a(12) from _Amiram Eldar_, Aug 18 2023