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%I #9 Dec 01 2013 15:41:56
%S 1,19684,1953126,40353608,387440173,2357947692,10604499374,
%T 38445332184,118587876498,322687697780,794320419872,1801152661464,
%U 3814699218751,7625984925160,14507145975870,26439622160672,46413842369328
%N a(n)=sigma_9(2n-1).
%H Harvey P. Dale, <a href="/A081866/b081866.txt">Table of n, a(n) for n = 1..1000</a>
%t DivisorSigma[9,Range[1,41,2]] (* _Harvey P. Dale_, Dec 01 2013 *)
%Y Cf. A013957.
%K nonn
%O 1,2
%A _Benoit Cloitre_, Apr 12 2003