20190206, 09:58  #1 
Mar 2018
2·5·53 Posts 
Pg primes with exponent multiple of 201
The pg(k) numbers are formed by the concatenation of two consecutive Mersenne numbers...
pg(k)=(2^k1)*10^d+2^(k1)1 where d is the number of decimal digits of 2^(k1)1 example pg(1)=10 pg(2)=31 pg(3)=73... Consider when k is multiple of 201 and pg(k) is prime. This happens for k=6231 and k=51456 6231/61 and 51456/61 will have the same 60 digit repeating term 147540...2131. Why? 
20190206, 10:03  #2 
Jun 2003
3·17·101 Posts 
What does 1/61 look like?
Last fiddled with by enzocreti on 20190206 at 10:13 
20190206, 10:14  #3 
Mar 2018
2×5×53 Posts 
THE SAME?
the same?

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