%I #9 Mar 29 2016 04:22:03
%S 2,3,5,7,11,66,101,131,151,181,191,222,282,313,353,373,383,434,474,
%T 494,555,595,606,646,727,757,777,787,797,919,929,969,1001,1221,1551,
%U 1771,2222,2882,3333,3553,4334,4994,5335,5555,5665,5885,5995,6006,6226,6446
%N Palindromic numbers which are products of an odd number of distinct primes.
%H Chai Wah Wu, <a href="/A075800/b075800.txt">Table of n, a(n) for n = 1..10000</a>
%e 191 is palindromic and prime, 222=2*3*37 is palindromic and a product of 3 distinct primes.
%p test := proc(n) local d; d := convert(n,base,10); return ListTools[Reverse](d)=d and numtheory[mobius](n)=-1; end; a := []; for n from 1 to 7000 do if test(n) then a := [op(a),n]; end; od; a;
%Y Cf. A002385, A069217, A032350, A030059.
%K nonn,base
%O 1,1
%A _Jani Melik_, Oct 13 2002
%E Edited by _Dean Hickerson_, Oct 21 2002
|