A075799 - OEIS

%I #6 Jun 24 2014 01:08:26

%S 1,6,22,33,55,77,111,141,161,202,262,303,323,393,454,505,515,535,545,

%T 565,626,707,717,737,767,818,838,858,878,898,939,949,959,979,989,1111,

%U 1441,1661,1991,2002,2442,3003,3113,3223,3443,3883,4774,5005,5115,6666

%N Palindromic numbers which are products of an even number of distinct primes.

%e 1, 111=3*37 and 858=2*3*11*13 are palindromic and products of an even number of 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. A046392, A002385, A069217, A032350, A030229.

%K nonn,base

%O 1,2

%A _Jani Melik_, Oct 13 2002

%E Edited by _Dean Hickerson_, Oct 21 2002