Monday 28 November 2016

Truncatable primes

Two sequences of prime numbers:

7
73
739
7393
73939
739391

7
37
137
9137
29137
629137
646216567629137
2646216567629137
12646216567629137
312646216567629137
6312646216567629137
86312646216567629137
686312646216567629137
7686312646216567629137
57686312646216567629137
357686312646216567629137