%I #19 Mar 23 2017 14:40:11
%S 1,2,2,2,6,6,3,3,3,4,15,4,5,20,5,30,30,6,6,6,6,8,24,24,8,8,8,8,10,72,
%T 72,10,110,90,99,11,110,11,132,132,12,12,12,12,12,16,70,154,112,48,84,
%U 112,112,14,16,112,16,16,16,16,20,272,238,357,304,272,380,20,340,357,399
%N a(n) = lcm(q(n - q(n+1) + 2), q(n - q(n) + 2)) where q(n) = A005185(n).
%C See the order of chaotic subsequences in scatterplot link.
%H Altug Alkan, <a href="/A283673/b283673.txt">Table of n, a(n) for n = 1..10000</a>
%H Altug Alkan, <a href="/A283673/a283673.png">Alternative Scatterplot of A283673</a>
%e a(4) = lcm(A005185(4 - A005185(5) + 2), A005185(4 - A005185(4) + 2)) = lcm(A005185(3), A005185(3)) = lcm(2, 2) = 2.
%t q[1] = q[2] = 1; q[n_] := q[n] = q[n - q[n - 1]] + q[n - q[n - 2]]; Table[LCM[q[n - q[n + 1] + 2], q[n - q[n] + 2]], {n, 71}] (* _Indranil Ghosh_, Mar 14 2017 *)
%o (PARI) 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, lcm(a[n+2-a[n+1]],a[n+2-a[n]]))
%Y Cf. A005185, A283672, A283677.
%K nonn,look
%O 1,2
%A _Altug Alkan_, Mar 14 2017
|