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A333424
Primes that are palindromes in primorial base.
2
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
1,1
EXAMPLE
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.
MATHEMATICA
max = 8; bases = Prime @ Range[max, 1, -1]; nmax = Times @@ bases - 1; Select[Range[nmax], PrimeQ[#] && PalindromeQ @ IntegerDigits[#, MixedRadix[bases]] &]
KEYWORD
nonn
AUTHOR
Amiram Eldar, Mar 20 2020
STATUS
approved