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%I #13 Mar 21 2020 09:40:27
%S 1,2,2,2,2,2,2,2,2,2,2,2,2,2,6,2,2,2,2,2,2,2,2,4,2,2,2,2,2,2,2,2,2,2,
%T 2,6,2,2,6,2,2,2,2,2,2,12,4,2,2,2,2,2,2,6,6,2,2,2,2,2,2,2,2,2,2,2,2,2,
%U 2,2,2,2,6,2,2,2,4,4,2,2,2,2,2,2,2,2,4,2,2,4,4,4,4,4,2,6,2,2,6,2,2,6,2,2
%N GCD of n-th and (n+1)-st term in the sequence of first differences between primes, A001223.
%F a(n) = gcd( A001223(n+1), A001223(n) ).
%t Map[GCD @@ # &, Partition[#, 2, 1] &@ Differences@ Prime@ Range@ 100] (* _Michael De Vlieger_, Feb 18 2017 *)
%Y Cf. A001223.
%K nonn,easy
%O 1,2
%A _Labos Elemer_, Dec 06 2000