A333424 Primes that are palindromes in primorial base.
3, 7, 11, 31, 47, 211, 223, 229, 281, 293, 2311, 2347, 2383, 2843, 2879, 30091, 30181, 30211, 30307, 30367, 30427, 30493, 30553, 30643, 30829, 30859, 34871, 34961, 35051, 35117, 35267, 35363, 35393, 35423, 510751, 511711, 513067, 513307, 515143, 517459, 518179
Offset: 1
Keywords
Examples
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.
Links
- Amiram Eldar, Table of n, a(n) for n = 1..300
- Wikipedia, Primorial number system.
- Index entries for sequences related to primorial base.
Crossrefs
Programs
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Mathematica
max = 8; bases = Prime @ Range[max, 1, -1]; nmax = Times @@ bases - 1; Select[Range[nmax], PrimeQ[#] && PalindromeQ @ IntegerDigits[#, MixedRadix[bases]] &]