%I #10 Mar 30 2012 17:34:13
%S 1,1,2,3,3,3,4,4,4,4,6,5,6,6,6,6,8,7,8,8,8,8,8,8,11,9,9,11,11,11,11,
%T 11,11,11,11,14,12,11,12,14,14,14,14,14,14,14,14,14,14,17,15,14,14,17,
%U 17,15,17,17,17,17,17,17,17,17,17,17,21,18,17,17,21,20,17,21,21,21,18,21
%N a(n) = a(a(a(n - a(n-1)))) + a(n - a(n-2)).
%C A fourth-order recursive version of Hofstadter Q of the first term of A005185.
%H Paolo P. Lava, <a href="/A087842/b087842.txt">Table of n, a(n) for n = 1..10000</a>
%t digits=200 Hofstadter[n_Integer?Positive] := Hofstadter[n] = Hofstadter[Hofstadter[Hofstadter[n - Hofstadter[n-1]]]] + Hofstadter[n - Hofstadter[n-2]] Hofstadter[1] = Hofstadter[2] = 1 a1=Table[Hofstadter[n], {n, 1, digits}]
%Y Cf. A005185.
%K nonn
%O 1,3
%A _Roger L. Bagula_, Oct 07 2003
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