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%I #14 Mar 23 2017 12:07:28
%S 1,1,1,2,1,1,3,3,3,4,1,4,5,1,5,1,1,6,6,6,6,8,2,2,8,8,8,8,10,1,1,10,1,
%T 1,1,11,1,11,1,1,12,12,12,12,12,16,2,1,2,4,2,2,2,14,16,2,16,16,16,16,
%U 20,1,1,1,1,1,1,20,1,1,1,1,1,1,2,1,1,1,22,1,1,23,1,1,1,1,23,24
%N a(n) = gcd(q(n - q(n+1) + 2), q(n - q(n) + 2)) where q(n) = A005185(n).
%H Altug Alkan, <a href="/A283672/b283672.txt">Table of n, a(n) for n = 1..10000</a>
%H Altug Alkan, <a href="/A283672/a283672.png">Alternative Scatterplot of A283672</a>
%e a(4) = gcd(A005185(4 - A005185(5) + 2), A005185(4 - A005185(4) + 2)) = gcd(A005185(3), A005185(3)) = gcd(2, 2) = 2.
%t q[1] = q[2] = 1; q[n_] := q[n] = q[n - q[n - 1]] + q[n - q[n - 2]]; Table[GCD[q[n - q[n + 1] + 2], q[n - q[n] + 2]], {n, 88}] (* _Indranil Ghosh_, Mar 14 2017 *)
%o a=vector(1001); a[1]=a[2]=1; for(n=3, #a, a[n]=a[n-a[n-1]]+a[n-a[n-2]]); va = vector(1000, n, gcd(a[n+2-a[n+1]], a[n+2-a[n]]))
%Y Cf. A005185, A283673.
%K nonn
%O 1,4
%A _Altug Alkan_, Mar 14 2017
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