A075809 Palindromic even numbers with an odd number of distinct prime factors.

2, 66, 222, 282, 434, 474, 494, 606, 646, 2222, 2882, 4334, 4994, 6006, 6226, 6446, 6886, 8338, 8558, 8778, 8998, 20002, 20202, 20702, 20802, 20902, 22222, 22922, 24042, 24342, 24542, 24742, 24942, 26062, 26162, 26462, 28082, 28182, 28282

Offset: 1

Author

Jani Melik, Oct 13 2002

Keywords

• nonn
• base
• look

Examples

			66=2*3*11, 222=2*3*37 and 282=2*3*47 are palindromic, even and products of an odd number of distinct primes.
		

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A053858.

Programs

Maple

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 2 to 30000 by 2 do if test(n) then a := [op(a),n]; end; od; a;

Extensions

Edited by Dean Hickerson, Oct 21 2002