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%I #24 May 22 2022 05:50:17
%S 25,125,295,625,1475,2995,3125,3481,7375,14975,15625,17405,35341,
%T 36875,74875,78125,87025,176705,184375,205379,299995,358801,374375,
%U 390625,435125,479795,497795,883525,921875,1026895,1499975,1794005,1871875
%N Composite numbers whose prime factors contain no digits other than 5 and 9.
%C All terms are a product of at least two terms of A020468. - _David A. Corneth_, Oct 09 2020
%H David A. Corneth, <a href="/A036321/b036321.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Pri#prime_factors">Index entries for sequences related to prime factors</a>.
%F Sum_{n>=1} 1/a(n) = Product_{p in A020468} (p/(p - 1)) - Sum_{p in A020468} 1/p - 1 = 0.0550718517... . - _Amiram Eldar_, May 22 2022
%t Select[Range[1872000],CompositeQ[#]&&SubsetQ[{5,9},Flatten[ IntegerDigits/@ FactorInteger[#][[All,1]]]]&] (* _Harvey P. Dale_, Sep 17 2019 *)
%Y Cf. A020468, A036302-A036325.
%K nonn,easy,base
%O 1,1
%A _Patrick De Geest_, Dec 15 1998
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