Open main menu
Home
Random
Recent changes
Special pages
Community portal
Preferences
About Wikipedia
Disclaimers
Incubator escapee wiki
Search
User menu
Talk
Dark mode
Contributions
Create account
Log in
Editing
Look-and-say sequence
(section)
Warning:
You are not logged in. Your IP address will be publicly visible if you make any edits. If you
log in
or
create an account
, your edits will be attributed to your username, along with other benefits.
Anti-spam check. Do
not
fill this in!
=== Growth in length === The terms eventually grow in length by about 30% per generation. In particular, if ''L''<sub>''n''</sub> denotes the number of digits of the ''n''-th member of the sequence, then the [[Limit (mathematics)|limit]] of the ratio <math>\frac{L_{n + 1}}{L_n}</math> exists and is given by <math display="block">\lim_{n \to \infty} \frac{L_{n+1}}{L_{n}} = \lambda</math> where λ = 1.303577269034... {{OEIS|id=A014715}} is an [[algebraic number]] of degree 71.<ref name="Martin2006" /> This fact was proven by Conway, and the constant λ is known as '''Conway's constant'''. The same result also holds for every variant of the sequence starting with any seed other than 22. ==== Conway's constant as a polynomial root ==== Conway's constant is the unique positive [[real root]] of the following [[polynomial]] {{OEIS|id=A137275}}: <math display="block">\begin{matrix} & &\qquad & &\qquad & &\qquad & & +1x^{71} & \\ -1x^{69} & -2x^{68} & -1x^{67} & +2x^{66} & +2x^{65} & +1x^{64} & -1x^{63} & -1x^{62} & -1x^{61} & -1x^{60} \\ -1x^{59} & +2x^{58} & +5x^{57} & +3x^{56} & -2x^{55} & -10x^{54} & -3x^{53} & -2x^{52} & +6x^{51} & +6x^{50} \\ +1x^{49} & +9x^{48} & -3x^{47} & -7x^{46} & -8x^{45} & -8x^{44} & +10x^{43} & +6x^{42} & +8x^{41} & -5x^{40} \\ -12x^{39} & +7x^{38} & -7x^{37} & +7x^{36} & +1x^{35} & -3x^{34} & +10x^{33} & +1x^{32} & -6x^{31} & -2x^{30} \\ -10x^{29} & -3x^{28} & +2x^{27} & +9x^{26} & -3x^{25} & +14x^{24} & -8x^{23} & & -7x^{21} & +9x^{20} \\ +3x^{19} & -4x^{18} & -10x^{17} & -7x^{16} & +12x^{15} & +7x^{14} & +2x^{13} & -12x^{12} & -4x^{11} & -2x^{10} \\ +5x^{9} & & +1x^{7} & -7x^{6} & +7x^{5} & -4x^{4} & +12x^{3} & -6x^{2} & +3x^{1} & -6x^{0} \\ \end{matrix} </math> This polynomial was correctly given in Conway's original ''Eureka'' article,<ref name="Conway-original-article" /> but in the reprinted version in the book edited by Cover and Gopinath<ref name="Conway-original-article" /> the term <math>x^{35}</math> was incorrectly printed with a minus sign in front.<ref> {{Cite book | last = Vardi | first = Ilan | title = Computational Recreations in Mathematica | publisher = [[Addison-Wesley]] | year = 1991 | isbn = 0-201-52989-0 }} </ref>
Edit summary
(Briefly describe your changes)
By publishing changes, you agree to the
Terms of Use
, and you irrevocably agree to release your contribution under the
CC BY-SA 4.0 License
and the
GFDL
. You agree that a hyperlink or URL is sufficient attribution under the Creative Commons license.
Cancel
Editing help
(opens in new window)