A046402 Numbers with exactly 4 distinct palindromic prime factors.

210, 330, 462, 770, 1155, 3030, 3930, 4242, 4530, 5430, 5502, 5730, 6342, 6666, 7070, 7602, 8022, 8646, 9170, 9390, 9966, 10570, 10590, 10605, 11110, 11190, 11490, 11946, 12606, 12670, 13146, 13370, 13755, 14410, 14826, 15554, 15666, 15855, 16086, 16610, 16665

Offset: 1

Author

Patrick De Geest, Jun 15 1998

Keywords

• nonn
• base

Links

• Andrew Howroyd, Table of n, a(n) for n = 1..1000

Crossrefs

Intersection of A033620 and A046386.

Cf. A046370.

Programs

Mathematica

Take[Times@@@Module[{nn=300,pp},pp=Select[Prime[Range[nn]],PalindromeQ];Subsets[pp,{4}]]//Union,40] (* Harvey P. Dale, Aug 13 2024 *)

Extensions

Offset changed and a(37) onwards from Andrew Howroyd, Aug 14 2024