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A335934
Smallest palindrome in base 10 whose factorization contains n distinct base 10 palindromic prime factors.
0
1, 2, 6, 66, 2772, 279972, 67566576, 5159488849515, 83797355379738
OFFSET
0,2
COMMENTS
For n <= 6, a(n) does not have a non-palindromic prime factor, i.e. a(n) has n distinct prime factors and they are all palindromes. On the other hand, a(7) contains a prime factor 13, which is not a palindrome.
EXAMPLE
a(6) = 67566576 = 2^4*3*7*11*101*181 has 6 distinct palindromic prime factors.
CROSSREFS
KEYWORD
nonn,hard,base
AUTHOR
Chai Wah Wu, Jun 30 2020
EXTENSIONS
a(8) from David A. Corneth, Jul 01 2020
STATUS
approved