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%I #11 Aug 01 2019 03:47:52
%S 1,2,3,4,3,2,5,2,5,6,5,4,7,2,7,10,3,2,3,11,13,11,13,3,2,3,4,17,2,17,6,
%T 5,2,5,2,13,6,7,2,7,19,21,19,2,19,4,3,10,23,2,23,4,5,2,3,2,3,2,29,31,
%U 29,31,2,3,4,11,2,7,6,7,6,7,6,7,2,35,37,35
%N a(n) = gcd(A098550(n+2), A098550(n)).
%C For n > 1: a(n) > 1, by definition of A098550;
%C gcd(a(n+1), a(n)) = 1;
%C gcd(a(n), A098550(n)) = a(n).
%H Reinhard Zumkeller, <a href="/A251102/b251102.txt">Table of n, a(n) for n = 1..10000</a>
%o (Haskell)
%o a251102 n = a251102_list !! (n-1)
%o a251102_list = zipWith gcd (drop 2 a098550_list) a098550_list
%Y Cf. A098550, A253581.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Nov 30 2014