Palindromic wing primes (a.k.a. near-repdigit palindromic primes) of the general form r*(10^d - 1)/9 + (m-r)*10^floor(d/2) where d is the number of digits (an odd number > 1), r is the repeated digit, and m (different from r) is the middle digit.
A077798
Palindromic wing primes (a.k.a. near-repdigit palindromic primes) of the general form r*(10^d - 1)/9 + (m-r)*10^floor(d/2) where d is the number of digits (an odd number > 1), r is the repeated digit, and m (different from r) is the middle digit.
Terms
- a(0) =101a(1) =131a(2) =151a(3) =181a(4) =191a(5) =313a(6) =353a(7) =373a(8) =383a(9) =727a(10) =757a(11) =787a(12) =797a(13) =919a(14) =929a(15) =11311a(16) =11411a(17) =33533a(18) =77377a(19) =77477a(20) =77977a(21) =1114111a(22) =1117111a(23) =3331333a(24) =3337333a(25) =7772777a(26) =7774777a(27) =7778777a(28) =111181111a(29) =111191111
External references
- oeis: A077798