8666668

Appears in sequences

• Nontrivial palindromes k such that phi(k) is also a palindrome.at n=14A067723
• Numbers n such that n and phi(n) are both palindromes.at n=23A069747
• a(n) is equal to the number of positive integers m less than or equal to 10^n such that m is not divisible by at least one of the primes 2,7 and is not divisible by at least one of the primes 3,5.at n=5A128956