Thread: 3, 7, 31, 127
View Single Post
Old 2019-04-03, 07:40   #3
lukerichards
 
lukerichards's Avatar
 
"Luke Richards"
Jan 2018
Birmingham, UK

4408 Posts
Default

Only known instance where four consecutive primes, p, for which 2p-1 is prime?

That is, where pn is the nth prime and M(x) represents 2x-1, then:

M(pn)
M(pn+1)
M(pn+2)
M(pn+3)

are all prime.
lukerichards is offline   Reply With Quote