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a[n] =a[Min[n-1,Abs[n - a[n-1]]]] + a[a[a[Abs[n - a[n-3]]]]]
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%I #4 Mar 30 2012 17:34:13

%S 1,1,1,2,2,3,3,3,4,4,4,4,5,5,5,5,5,6,6,6,6,6,6,7,7,7,7,7,7,7,8,8,8,8,

%T 8,8,8,8,9,9,9,9,9,9,9,9,9,11,10,11,11,11,11,11,11,11,11,11,13,11,13,

%U 12,13,13,13,13,13,13,13,13,13,15,13,15,13,15,14,15,15,15,15,15,15,15,15

%N a[n] =a[Min[n-1,Abs[n - a[n-1]]]] + a[a[a[Abs[n - a[n-3]]]]]

%C The fourth recursive of the second term of the skip one Hofstadter Q.

%t Hofstadter3[n_Integer?Positive] := Hofstadter3[n] = Hofstadter3[Min[n-1, Abs[n - Hofstadter3[n-1]]]] + Hofstadter3[Hofstadter3[Hofstadter3[Abs[n - Hofstadter3[n-3]]]]] Hofstadter3[0]=Hofstadter3[1] = Hofstadter3[2]= Hofstadter3[3]= 1 digits=200 ta=Table[Hofstadter3[n], {n, 1, digits}]

%Y Cf. A005185, A081831.

%K nonn

%O 1,4

%A _Roger L. Bagula_, Oct 07 2003