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%I #13 Jan 20 2016 17:53:41
%S 1,1,1,1,2,2,3,3,3,4,4,4,4,5,5,5,5,5,6,6,6,6,6,6,7,7,7,7,7,7,7,8,8,8,
%T 8,8,8,8,8,9,9,9,9,9,9,9,9,9,10,10,10,10,10,10,10,10,10,10,11,11,11,
%U 11,11,11,11,11,11,11,11,12,12,12,12,12,12,12,12,12,12,12,12,13,13,13,13,13
%N a(n) = a(|n - a(n-1)|) + a(a(a(|n - a(n-4)|))).
%C The skip two term two fourth recursion of the Hofstadter Q.
%C The conjecture is that even higher order recursions of the term one and term two type for the original and skip term versions of A005185 Hofstadter Q will exist as well. I have invented this way of naming the larger generalization of Hofstadter Q type sequences as being descriptive of their formation.
%C From which numbers n>3 on is this sequence different from A002024(n-3), if ever? - _M. F. Hasler_, Apr 19 2014
%t Hofstadter14[n_Integer?Positive] := Hofstadter14[n] = Hofstadter14[Abs[n - Hofstadter14[n-1]]] + Hofstadter14[Hofstadter14[ Hofstadter14[Abs[n - Hofstadter14[n-4]]]]] Hofstadter14[0] = Hofstadter14[1] = Hofstadter14[2]= Hofstadter14[3]= Hofstadter14[4]= 1 digits=200 ta=Table[Hofstadter14[n], {n, 1, digits}]
%o (PARI) a(n) = if(n<5, return(1)); a(abs(n - a(n-1))) + a(a(a(abs(n - a(n-4))))) \\ _Charles R Greathouse IV_, Jan 20 2016
%Y Cf. A005185, A081831.
%K nonn
%O 1,5
%A _Roger L. Bagula_, Oct 07 2003
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