19391

Properties

Appears in sequences

• Palindromic primes: prime numbers whose decimal expansion is a palindrome.at n=43A002385
• Primes that remain prime through 3 iterations of function f(x) = 2x + 9.at n=37A023276
• Palindromic prime lengths of factorials: see A035067.at n=19A035068
• Palindromic primes containing no pair of consecutive equal digits.at n=37A050784
• Palindromic Sophie Germain primes.at n=8A051835
• Palindromic primes whose sum of squared digits is also prime.at n=19A052035
• Primes such that prime(p) +- pi(p) are simultaneously prime.at n=32A065117
• Numbers such that every cyclic permutation is a prime.at n=34A068652
• Let p = abc..k be a prime in base 10. Define mirror(p) = abc...k...cba. Sequence gives primes of the form mirror(p) for some p.at n=12A068686
• Palindromic primes with prime middle digit.at n=21A076611
• Palindromic primes with middle digit 3.at n=7A082439
• Palindromic Sophie Germain primes: both p and 2p+1 are palindromic primes.at n=4A082520
• Palindromic prime units W appearing twice in first-order fractal palindromic primes WmW.at n=22A082598
• a(n) = smallest palindromic prime that begins with A082768(n) and contains more than twice the number of digits in A082768(n), or 0 if no such number exists.at n=13A082770
• Palindromes which are prime and the sum of the digits is also prime.at n=27A082806
• Palindromic primes p with property that another palindromic prime with as many digits can be obtained by using all the digits of p with a different frequency >=1 (every digit is used at least once).at n=13A082807
• Smallest palindromic prime beginning with the n-th prime, or 0 if no such prime exists.at n=43A088249
• Palindromic primes that yield a prime when sandwiched between two 1's. (Prefixing and suffixing a 1 on both sides yields another palindromic prime.)at n=8A088269
• Palindromic primes that yield a prime when sandwiched between two 3's. (Prefixing and suffixing a -three' on both sides yields another pal prime).at n=15A088270
• Prime mean of 8 horizontal, vertical and main diagonal sums associated with primes in A094454.at n=23A094455