in the 1st attempt the solution appears to be
(n+1)! + 2 to (n+1)!+n+1 the kth term is divisible k+1
but it can be bettered as
LCM(2,3,... n+1) + 2 to
LCM(2,3,... n+1) + n+ 1
and LCM(2,3,... n+1) is the lower of the two
It can still be bettered to the product of all primes (<= n+1)say P(n) + 2 to that + n+ 1
as the number from 2 to n+1 if a prime the product has that prime as a factor
and if not a prime then P(n) and and k have a common factor so sum is not a prime
(one of my friends informed me)
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