5236153domain: NAppears in sequencesa(n) is the smallest m such that m < 10^n, 10^n + m is prime and if the natural number k is such that 1 < k < 10 and 3 doesn't divide k*10^n + m then k*10^n+m is prime.at n=12A078728Numbers n such that A001414(n) divides n+1 and A001414(n+1) divides n.at n=28A131484