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%I #7 Apr 07 2024 09:09:44
%S 3,6,8,11,12,16,16,20,21,24,24,30,28,32,34,37,36,42,40,46,46,48,48,56,
%T 53,56,58,62,60,68,64,70,70,72,74,81,76,80,82,88,84,92,88,94,96,96,96,
%U 106,101,106,106,110,108,116,114,120,118,120,120,132,124,128,132,135,134,140
%N a(n) = 2*n + tau(n).
%t a[n_] := 2*n + DivisorSigma[0, n]; Array[a, 100] (* _Amiram Eldar_, Apr 07 2024 *)
%o (PARI) a(n) = 2*n + numdiv(n); \\ _Amiram Eldar_, Apr 07 2024
%Y Cf. A000005 (tau), A140481, A062249.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, Jun 29 2008