for which values of p this expression has the form s*2^k?
let be p an arbitrary prime...
can you find values of p such that
(10^p1)/9+1 has the form s*2^k?
where s is a prime and k an integer >0
example p=3 does the job
infact (10^31)/9+1 has the form 7*2^4
p=5 does not the job because
(10^51)/9+1 has the form 2^3*3*463...
