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

1,1

Links

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

Example

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.

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;

Crossrefs

Cf. A053858.

Sequence in context: A333677 A098089 A304934 * A257788 A349108 A226409

Adjacent sequences: A075806 A075807 A075808 * A075810 A075811 A075812

Keyword

nonn,base,look

Author

Jani Melik, Oct 13 2002

Extensions

Edited by Dean Hickerson, Oct 21 2002

Status

approved