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A046395 Palindromes with exactly 5 distinct prime factors. 3

%I #13 Apr 09 2021 11:13:06

%S 6006,8778,20202,28182,41514,43134,50505,68586,87978,111111,141141,

%T 168861,202202,204402,209902,246642,249942,262262,266662,303303,

%U 323323,393393,399993,438834,454454,505505,507705,515515,516615,519915,534435,535535,543345

%N Palindromes with exactly 5 distinct prime factors.

%C 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

%H Harvey P. Dale, <a href="/A046395/b046395.txt">Table of n, a(n) for n = 1..500</a>

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

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

%Y Cf. A046331.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Jun 15 1998

%E Corrected at the suggestion of Sean A. Irvine by _Harvey P. Dale_, Apr 09 2021

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Last modified April 24 19:39 EDT 2024. Contains 371963 sequences. (Running on oeis4.)