M is the smallest possible sum for a set of four distinct primes such that the sum of any three is prime - (p1,p2,p3,p4}.
N is the smallest possible sum for a set of six distinct primes such that the sum of any five is prime - (q1,q2,q3,q4,q5,q6}.
Find M & N and the
corresponding sets.
An even easier proof that 5 is impossible.
Pick any four numbers in the set that do not include 2. There is always at least one such set. They are all odd and sum to a non-prime even number.
q.e.d.