OFFSET
1,1
COMMENTS
The asymptotic density of this sequence is 19/108. - Amiram Eldar, Jan 16 2022
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
MATHEMATICA
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 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Dec 04 2009
EXTENSIONS
Extended beyond 150 by R. J. Mathar, Dec 09 2009
STATUS
approved