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A063892 a(1) = a(2) = a(3) = 1, a(n) = a(n-a(n-2))+a(n-a(n-3)) for n>3.

%I A063892 #8 Apr 15 2014 20:16:03
%S A063892 1,1,1,2,4,6,5,3,3,9,6,4,7,12,9,5,7,10,16,16,10,12,12,16,14,21,13,17,
%T A063892 8,14,24,26,19,12,8,23,22,23,12,17,18,28,35,26,16,22,34,47,22,6,10,36,
%U A063892 69,36
%N A063892 a(1) = a(2) = a(3) = 1, a(n) = a(n-a(n-2))+a(n-a(n-3)) for n>3.
%C A063892 Undefined for n>54 since a(53)=69>=55.
%e A063892 a(7) = a(7-a(5))+a(7-a(4)) = a(7-4)+a(7-2) = a(3)+a(5) = 1+4 = 5.
%p A063892 #Q(r,s) with initial values 1,1,1,..., from _N. J. A. Sloane_, Apr 15 2014
%p A063892 r:=2; s:=3;
%p A063892 a:=proc(n) option remember; global r,s;
%p A063892 if n <= s then 1
%p A063892 else
%p A063892     if (a(n-r) <= n) and (a(n-s) <= n) then
%p A063892     a(n-a(n-r))+a(n-a(n-s));
%p A063892     else lprint("died with n =",n); return (-1);
%p A063892     fi;
%p A063892 fi; end;
%p A063892 [seq(a(n),n=1..54)];
%Y A063892 Cf. A005185, A046700, A063882, A226222.
%Y A063892 See A064714 for a variant which does not die.
%K A063892 fini,full,nonn
%O A063892 1,4
%A A063892 _Henry Bottomley_, Aug 29 2001