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%I #13 Jan 16 2022 08:19:09
%S 4,6,9,20,28,30,42,44,45,52,63,66,68,76,78,92,99,100,102,114,116,117,
%T 124,138,140,148,150,153,164,171,172,174,186,188,196,207,210,212,220,
%U 222,225,236,244,246,258,260,261,268,279,282,284,292,294,308,315,316
%N Numbers k such that A169611(k) = 2.
%C The asymptotic density of this sequence is 19/108. - _Amiram Eldar_, Jan 16 2022
%H Amiram Eldar, <a href="/A171127/b171127.txt">Table of n, a(n) for n = 1..10000</a>
%t f[n_] := Plus @@ Last /@ Select[ FactorInteger@ n, 1 < #[[1]] < 4 &]; Select[ Range@ 317, f@# == 2 &] (* _Robert G. Wilson v_, Dec 19 2009) (* Extended beyond 150 by _R. J. Mathar_, Dec 09 2009 *)
%Y Cf. A169611.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Dec 04 2009
%E Extended beyond 150 by _R. J. Mathar_, Dec 09 2009