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%I #16 Jun 19 2022 12:52:41
%S 0,31,225,1563,10222,63030,374264,2160300,12196405,67724342,371233523,
%T 2014305995
%N Total number of composite numbers with n digits and n prime factors (counted with multiplicity).
%C Essentially the same as A124033.
%H Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_025.htm">Puzzle 25. Composed primes (by G.L. Honaker, Jr.)</a>, The Prime Puzzles and Problems Connection. (A related puzzle.)
%e a(1) = 0, since any single-digit number with 1 prime factor is a prime!
%t Table[Total[Table[If[CompositeQ[n]&&PrimeOmega[n]==x,1,0],{n,10^(x-1),10^x-1}]],{x,8}] (* The program generates the first 8 terms of the sequence. *) (* _Harvey P. Dale_, Jun 19 2022 *)
%Y Cf. A036336, A036337, A036338.
%K nonn,base,more
%O 1,2
%A _Patrick De Geest_, Dec 15 1998
%E One more term from _Naohiro Nomoto_, Jul 31 2001
%E a(9)-a(12) from _Ray Chandler_, Apr 12 2011
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