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A240822 a(n) = index of first nonexisting term of the meta-Fibonacci sequence {f(k) = k for k <= n; f(k)=f(k-f(k-1))+f(k-f(k-n))} if that sequence is only defined for finitely many terms, or 0 if that sequence is infinite.

%I A240822 #19 Sep 19 2023 15:41:43
%S A240822 7,0,163,0,57,2350,277,1301,85,1246,357,409,487,471,765,1173,259,357,
%T A240822 806,820,1079,2100,471,2594,663,1171,666,1086,2105,1418,725,1197,1248,
%U A240822 1629,649,2241,713,2305,1837,1425,1083,2760,1265,1571,2236,1513,1443,2448
%N A240822 a(n) = index of first nonexisting term of the meta-Fibonacci sequence {f(k) = k for k <= n; f(k)=f(k-f(k-1))+f(k-f(k-n))} if that sequence is only defined for finitely many terms, or 0 if that sequence is infinite.
%C A240822 a(2)=0 and a(4)=0 are conjectural.
%C A240822 Except for the two zero entries, this is equal to A240818(n)+1. See that entry for further information.
%C A240822 Similar to A134680 and A240810.
%H A240822 B. Balamohan, A. Kuznetsov and S. Tanny, <a href="http://www.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 A240822 D. R. Hofstadter, Curious patterns and non-patterns in a family of meta-Fibonacci recursions, Lecture in Doron Zeilberger's Experimental Mathematics Seminar, Rutgers University, April 10 2014; <a href="https://vimeo.com/91708646">Part 1</a>, <a href="https://vimeo.com/91710600">Part 2</a>.
%H A240822 <a href="/index/Ho#Hofstadter">Index entries for Hofstadter-type sequences</a>
%Y A240822 See A240818 for another version.
%Y A240822 A diagonal of the triangle in A240825.
%Y A240822 Cf. A134680, A240810.
%K A240822 nonn
%O A240822 1,1
%A A240822 _N. J. A. Sloane_, Apr 15 2014
%E A240822 More terms from _Max Alekseyev_, Sep 19 2023