Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A123199
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A123199 A special Bezier transform of the binomial triangle sequence using: x-> 2*x 1-x-> 1-x^2 t(n,m,x)=binomial[m, n]*(2*x)^n*(1-x^2)^(m - n). +0
1
1, 1, 2, -1, 1, 4, 2, -4, 1, 1, 6, 9, -4, -9, 6, -1, 1, 8, 20, 8, -26, -8, 20, -8, 1, 1, 10, 35, 40, -30, -68, 30, 40, -35, 10, -1, 1, 12, 54, 100, 15, -168, -76, 168, 15, -100, 54, -12, 1, 1, 14, 77, 196, 161, -238, -427, 184, 427, -238, -161, 196, -77, 14, -1, 1, 16, 104, 336, 476, -112, -1064, -432, 1222, 432, -1064, 112, 476 (list; graph; listen)
OFFSET

1,3

COMMENT

The ordinary Bezier transform is degenerate to 1 in all cases. This transform is pased on (x,1-x}->{2*x/(1+x^2),(1-x^2)/(1+x^2)} with has a sum of squares equal to one. This sequence is based on the similarity of Poncelet's trajectories using {2*x/(1+x^2),(1-x^2)/(1+x^2)} to de Casteljau's construction for Bezier-Bernstein Polynomials using (x,1-x}.

REFERENCES

Elliptic Curves, McKean and Moll, 1997, Cambridge University Press, page 106, figure 2.22

Over and Over Again, Chang and Sederberg,MAA,1997, page164, figure 26.1

FORMULA

Coeffiencts of: t(n,m,x)=binomial[m, n]*(2*x)^n*(1-x^2)^(m - n)

EXAMPLE

1

1, 2, -1

1, 4, 2, -4, 1

1, 6, 9, -4, -9, 6, -1

1, 8, 20, 8,-26, -8, 20,-8, 1

MATHEMATICA

x1 = 2*x; x2 = (1 - x^2); a = Table[Expand[Sum[Binomial[m, n]*x1^n*x2^(m - n), {n, 0, m}]], {m, 0, 10}]; w = Table[CoefficientList[a[[n]], x], {n, 1, 10}] Flatten[w]

CROSSREFS

Sequence in context: A129033 A054090 A122517 this_sequence A112096 A026725 A026758

Adjacent sequences: A123196 A123197 A123198 this_sequence A123200 A123201 A123202

KEYWORD

uned,sign

AUTHOR

Roger Bagula (rlbagulatftn(AT)yahoo.com), Oct 04 2006

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified July 23 17:35 EDT 2008. Contains 142285 sequences.


AT&T Labs Research