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Primes that are palindromes in primorial base.
2

%I #16 Mar 21 2020 07:13:03

%S 3,7,11,31,47,211,223,229,281,293,2311,2347,2383,2843,2879,30091,

%T 30181,30211,30307,30367,30427,30493,30553,30643,30829,30859,34871,

%U 34961,35051,35117,35267,35363,35393,35423,510751,511711,513067,513307,515143,517459,518179

%N Primes that are palindromes in primorial base.

%H Amiram Eldar, <a href="/A333424/b333424.txt">Table of n, a(n) for n = 1..300</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Mixed_radix#Primorial_number_system">Primorial number system</a>.

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>.

%e 3 is a term since it is a prime number and its representation in primorial base is 11 (1 * 2# + 1) which is a palindrome.

%t max = 8; bases = Prime @ Range[max, 1, -1]; nmax = Times @@ bases - 1; Select[Range[nmax], PrimeQ[#] && PalindromeQ @ IntegerDigits[#, MixedRadix[bases]] &]

%Y Intersection of A000040 and A333423.

%Y Cf. A049345, A235168.

%Y Cf. A002385, A016041, A029971, A029972, A029973, A029974, A029975, A029976, A029977, A029978, A029979, A029980, A029981, A029982, A333421.

%K nonn

%O 1,1

%A _Amiram Eldar_, Mar 20 2020