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A091986 a(0)=1, a(n) = sigma_3(2n). 3

%I

%S 1,9,73,252,585,1134,2044,3096,4681,6813,9198,11988,16380,19782,25112,

%T 31752,37449,44226,55261,61740,73710,86688,97236,109512,131068,141759,

%U 160454,183960,201240,219510,257544,268128,299593,335664,358722,390096,442845

%N a(0)=1, a(n) = sigma_3(2n).

%t Join[{1},Table[DivisorSigma[3,n],{n,2,80,2}]] (* _Harvey P. Dale_, Feb 26 2011 *)

%Y Bisection of A001158. Cf. A045823.

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Mar 20 2004

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Last modified January 21 21:55 EST 2022. Contains 350480 sequences. (Running on oeis4.)