Smallest k such that concatenation of r*k and 1 is a prime for all r = 1 to n but not prime for r = n+1, or smallest k such that 10*r*k+1 is a prime for all r = 1 to n but not prime for r = n+1.
A100986
Smallest k such that concatenation of r*k and 1 is a prime for all r = 1 to n but not prime for r = n+1, or smallest k such that 10*r*k+1 is a prime for all r = 1 to n but not prime for r = n+1.
Terms
- a(0) =1a(1) =3a(2) =21a(3) =33a(4) =1083a(5) =2541a(6) =822486a(7) =51282a(8) =1296060612
External references
- oeis: A100986