login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A240811 a(n) = length (or lifetime) of the meta-Fibonacci sequence f(1) = ... = f(n) = 1; f(k)=f(k-f(k-2))+f(k-f(k-n)) if that sequence is only defined for finitely many terms, or 0 if that sequence is infinite. 3

%I

%S 14,54,0,37,30,63,368,47,46,108,188,118,62,209,126,197,78,127,190,141,

%T 94,130,138,226,110,134,158,138,126,170,242,371,142,190,178,225,158,

%U 206,214,304,174,226,238,245,190,250,262,328,206,234,278,357,222,290

%N a(n) = length (or lifetime) of the meta-Fibonacci sequence f(1) = ... = f(n) = 1; f(k)=f(k-f(k-2))+f(k-f(k-n)) if that sequence is only defined for finitely many terms, or 0 if that sequence is infinite.

%C The term a(4) = 0 is only conjectural.

%D 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.

%H Lars Blomberg, <a href="/A240811/b240811.txt">Table of n, a(n) for n = 2..10000</a>, "infinity" = 10^8.

%H 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 D. R. Hofstadter, <a href="/A240811/a240811.pdf">Graph of first 100 terms</a>

%H <a href="/index/Ho#Hofstadter">Index entries for Hofstadter-type sequences</a>

%Y Cf. A063892, A087777, A240817 (sequences for n=3..5).

%Y See A240814 for another version.

%Y A diagonal of the triangle in A240813.

%K nonn

%O 2,1

%A _N. J. A. Sloane_, Apr 15 2014

%E More terms from _Lars Blomberg_, Oct 24 2014

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 20 13:10 EDT 2021. Contains 345164 sequences. (Running on oeis4.)