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A046395 Palindromes with exactly 5 distinct prime factors. 2
6006, 8778, 20202, 28182, 41514, 43134, 50505, 68586, 87978, 111111, 141141, 168861, 202202, 204402, 209902, 246642, 249942, 262262, 266662, 303303, 323323, 393393, 399993, 438834, 454454, 505505, 507705, 515515, 516615, 519915, 534435, 535535, 543345 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No exponent of the distinct prime factors can be greater than one, i.e., no prime powers are permitted. - Harvey P. Dale, Apr 09 2021 at the suggestion of Sean A. Irvine

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..500

EXAMPLE

505505 = 5 * 7 * 11 * 13 * 101.

MATHEMATICA

Select[Range[550000], PalindromeQ[#]&&PrimeNu[#]==PrimeOmega[#]==5&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Apr 09 2021 *)

CROSSREFS

Cf. A046331.

Sequence in context: A250514 A343432 A115429 * A143043 A031605 A239176

Adjacent sequences:  A046392 A046393 A046394 * A046396 A046397 A046398

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jun 15 1998

EXTENSIONS

Corrected at the suggestion of Sean A. Irvine by Harvey P. Dale, Apr 09 2021

STATUS

approved

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Last modified August 5 22:41 EDT 2021. Contains 346488 sequences. (Running on oeis4.)