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A046700 a(1) = a(2) = a(3) = 1, a(n) = a(n - a(n-1)) + a(n - a(n-3)) for 3 < n < 165.

%I A046700 #23 Dec 12 2016 07:30:08
%S A046700 1,1,1,2,3,4,4,5,5,7,6,8,7,9,8,10,9,12,9,12,10,15,11,16,12,17,13,18,
%T A046700 14,19,15,21,17,18,18,21,19,21,24,20,22,24,20,31,19,30,19,28,19,30,21,
%U A046700 32,21,34,21,36,21,38,21,48,18,53,15,49,18,49,24,61,17,51,19,42
%N A046700 a(1) = a(2) = a(3) = 1, a(n) = a(n - a(n-1)) + a(n - a(n-3)) for 3 < n < 165.
%D A046700 Sequence proposed by Reg Allenby.
%D A046700 Undefined past a(164), since a(164) = 202.
%H A046700 N. J. A. Sloane, <a href="/A046700/b046700.txt">Table of n, a(n) for n = 1..164</a> [The full sequence]
%H A046700 B. Balamohan, A. Kuznetsov and S. Tanny, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL10/Tanny/tanny3.html">On the behavior of a variant of Hofstadter's Q-sequence</a>, J. Integer Sequences, Vol. 10 (2007), #07.7.1.
%H A046700 <a href="/index/Ho#Hofstadter">Index entries for Hofstadter-type sequences</a>
%p A046700 V := proc(n) option remember; if n<=3 then 1 else if n > V(n-1) and n > V(n-3) then RETURN(V(n-V(n-1))+V(n-V(n-3))); else ERROR(" died at n= ", n); fi; fi; end;
%t A046700 a[1] = a[2] = a[3] = 1; a[n_] := a[n] = a[n - a[n - 1]] + a[n - a[n - 3]]; Array[a, 72] (* _Jean-François Alcover_, Dec 12 2016 *)
%K A046700 nonn,fini,full
%O A046700 1,4
%A A046700 _R. K. Guy_
%E A046700 Edited by _N. J. A. Sloane_, Nov 06 2007