211219

Properties

Appears in sequences

• Primes that are concatenations of n with n + 8.at n=24A032631
• Lucky numbers that are decimal concatenations of n with n + 8.at n=16A032658
• Odd numbers k such that the palindromic wing number (a.k.a. near-repdigit palindrome) 7*(10^k - 1)/9 - 2*10^((k-1)/2) is prime.at n=15A077785
• a(n) = A139602(m) such that for any k>m, A139602(k) > A139602(m).at n=25A189888
• a(n) = A047842(A047842(n)), say what you see, once repeated.at n=29A235775
• Primes formed from the concatenation of previousprime(n) and n.at n=21A280576
• Prime numbersat n=18911