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A240825 Triangle read by rows: T(n,k) (n >= 1, 1 <= k <= n) = index of first nonexisting term of the meta-Fibonacci sequence {f(i)=i for i <= n; thereafter f(i)=f(i-f(i-k))+f(i-f(i-n))} if that sequence is only defined for finitely many terms, or 0 if that sequence is infinite. 4
7, 0, 14, 163, 30, 21, 0, 0, 72, 28, 57, 30, 35, 36, 29, 2350, 25, 0, 29, 55, 42, 277, 51, 47, 45, 35, 56, 41, 1301, 0, 35, 0, 38, 69, 90 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The zero entries are only conjectural. More precisely, Hofstadter conjectures that T(n,k) = 0 (i.e. the sequence is immortal) iff n = 2k or n = 4k.

Apart from the zero entries, equals A240821 + 1.

REFERENCES

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.

LINKS

Table of n, a(n) for n=1..35.

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; Part 1, Part 2.

Index entries for Hofstadter-type sequences

EXAMPLE

Triangle begins:

7,

0,14,

163,30,21,

0,0,72,28,

57,30,35,36,29,

2350,25,0,29,55,42,

277,51,47,45,35,56,41,

1301,0,35,0,38,69,90, ...

...

CROSSREFS

Diagonals give A240822, A240823, A240824.

See A240821 for another version.

Sequence in context: A169603 A022920 A331423 * A243773 A097604 A240816

Adjacent sequences:  A240822 A240823 A240824 * A240826 A240827 A240828

KEYWORD

nonn,tabl,more

AUTHOR

N. J. A. Sloane, Apr 15 2014

STATUS

approved

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Last modified June 6 11:10 EDT 2020. Contains 334828 sequences. (Running on oeis4.)