Primes in which the unit place digit is 1 and the k-th most significant digit is prime (2,3,5,7) if k is prime else is composite (4,6,8,9,0).
A089704
Primes in which the unit place digit is 1 and the k-th most significant digit is prime (2,3,5,7) if k is prime else is composite (4,6,8,9,0).
Terms
- a(0) =31a(1) =71a(2) =251a(3) =271a(4) =331a(5) =521a(6) =571a(7) =751a(8) =4231a(9) =4271a(10) =4721a(11) =4751a(12) =6221a(13) =6271a(14) =6521a(15) =6551a(16) =6571a(17) =8221a(18) =8231a(19) =8521a(20) =8731a(21) =9221a(22) =9371a(23) =9521a(24) =9551a(25) =9721a(26) =20231a(27) =20521a(28) =20551a(29) =20731
External references
- oeis: A089704