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%I #11 Jan 28 2021 12:24:50
%S 99,171,333,343,363,555,575,595,747,777,909,969,1001,1221,1331,1551,
%T 1771,3333,3553,5335,5445,5555,5665,5775,5885,5995,7337,7557,7667,
%U 7777,7887,9009,9339,9559,9669,9779,9889,11211,11511,11711,11811,12121
%N Palindromic odd composite numbers with an odd number of prime factors (counted with multiplicity).
%H Harvey P. Dale, <a href="/A075815/b075815.txt">Table of n, a(n) for n = 1..1000</a>
%e 5445=3^2*5*11^2 and 5555=5*11*101 are palindromic, odd, composite and have an odd number of prime factors.
%p test := proc(n) local d; d := convert(n,base,10); return ListTools[Reverse](d)=d and type(numtheory[bigomega](n),odd) and not isprime(n); end; a := []; for n from 1 to 13000 by 2 do if test(n) then a := [op(a),n]; end; od; a;
%t Select[Range[9,13000,2],PalindromeQ[#]&&CompositeQ[#]&&OddQ[ PrimeOmega[ #]]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jan 28 2021 *)
%Y Cf. A046389.
%K nonn,base
%O 1,1
%A _Jani Melik_, Oct 13 2002
%E Edited by _Dean Hickerson_, Oct 21 2002