Determine the possible nonzero units digits of a duodecimal positive integer n such that:
Each of n and n+2 is a prime number, and:
n+2 is expressible as the sum of squares of two positive itegers.
(In reply to
heuristic computer exploration  no proof by Charlie)
Actually there are 19,289 such pairs that had been checked up through and including the pair 6104927, 6104929. The program had missed a few by checking for sums of squares only up to int(sqrt(N)/2) as the smaller one instead of int(sqrt(N/2)).
They all still check out with the same last duodecimal digit and the confirmation is stronger than before.

Posted by Charlie
on 20110922 21:38:05 