login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A120711 7 X 7 matrix Matrov of seven vertex Fano Plane: Characteristic polynomial : 12 + 10 x - 24 x^2 - 21 x^3 + 12 x^4 + 12 x^5 - x^7. 0
0, 14, 32, 150, 492, 1894, 6724, 24854, 89972, 329238, 1197972, 4372054, 15930580, 58096214, 211770452, 772129110, 2814859092, 10262536534, 37414140244, 136403674454, 497291840852, 1813006427478, 6609762501972, 24097566365014 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Limited here to seven connecting lines in the bonding graph.

REFERENCES

(*http://mathworld.wolfram.com/FanoPlane.html*)

LINKS

Table of n, a(n) for n=0..23.

FORMULA

M = {{0, 1, 0, 0, 0, 1, 1}, {1, 0, 1, 0, 0, 0, 1}, {0, 1, 0, 1, 0, 0, 1}, {0, 0, 1, 0, 1, 0, 1}, {0, 0, 0, 1, 0, 1, 1}, {1, 0, 0, 0, 1, 0, 1}, {1, 1, 1, 1, 1, 1, 0}} v[1] = {0, 1, 1, 2, 3, 5, 8} v[n_] := v[n] = M.v[n - 1] a(n) =v[n][[1]].

Empirical G.f.: 2*x*(7+16*x-2*x^2-14*x^3)/((1-x)*(1+x)*(1+2*x)*(1-2*x-6*x^2)). [Colin Barker, Mar 26 2012]

MATHEMATICA

M = {{0, 1, 0, 0, 0, 1, 1}, {1, 0, 1, 0, 0, 0, 1}, {0, 1, 0, 1, 0, 0, 1}, {0, 0, 1, 0, 1, 0, 1}, {0, 0, 0, 1, 0, 1, 1}, {1, 0, 0, 0, 1, 0, 1}, {1, 1, 1, 1, 1, 1, 0}} v[1] = {0, 1, 1, 2, 3, 5, 8} v[n_] := v[n] = M.v[n - 1] a = Table[v[n][[1]], {n, 1, 50}]

CROSSREFS

Cf. A111384.

Sequence in context: A084194 A031109 A155819 * A018959 A225420 A107484

Adjacent sequences:  A120708 A120709 A120710 * A120712 A120713 A120714

KEYWORD

nonn

AUTHOR

Roger L. Bagula, Aug 12 2006

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy .

Last modified February 21 14:29 EST 2018. Contains 299414 sequences. (Running on oeis4.)