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%I #9 Feb 05 2021 05:30:20
%S 2,6,5,5,7,17,9,11,11,13,13,23,15,26,17,17,19,19,20,22,22,23,25,26,26,
%T 29,29,33,31,41,32,34,35,35,37,54,38,44,41,43,43,44,45,47,47,53,49,96,
%U 51,53,52,55,55,64,57,57,59,59,61,91,62,67
%N Least k > n such that gcd(prime(n)+k, n+prime(k)) > 1.
%e a(2)=6 as: gcd(prime(2)+6,2+prime(6)) = gcd(3+6,2+13) = gcd(9,15) = 3 and gcd(prime(2)+k,2+prime(k))=1 for 2<k<6.
%o (PARI) a(n) = my(k=n+1); while(gcd(prime(n)+k, n+prime(k)) == 1, k++); k; \\ _Michel Marcus_, Feb 05 2021
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Jan 28 2002