[ November 11, 2006 ]
Two nice consecutive primes
Farideh Firoozbakht (email)

I found two nice  consecutive  primes p & q
related to the palindromic number 1551.

p = n^n – (n – 1)  and  q = n^n + (n – 1)

or

p = 1551¹⁵⁵¹ – (1551 – 1)  and  q = 1551¹⁵⁵¹ + (1551 – 1)

or

The next term (q) of A058912 is thus 1551.

I sent a similar email to Giovanni Resta and
he checked the primality of p & q with pfgw.
He wrote: " They are very nice indeed !
It was so difficult to believe in such a coincidence,
with numbers of 4949 digits, that I must confess
that I checked them with pfgw ! "