login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A042275 Denominators of continued fraction convergents to sqrt(663). 2
1, 1, 3, 4, 203, 207, 617, 824, 41817, 42641, 127099, 169740, 8614099, 8783839, 26181777, 34965616, 1774462577, 1809428193, 5393318963, 7202747156, 365530676763, 372733423919, 1110997524601, 1483730948520, 75297544950601, 76781275899121 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
FORMULA
G.f.: -(x^2-x-1)*(x^4+4*x^2+1) / (x^8-206*x^4+1). - Colin Barker, Dec 06 2013
a(n) = 206*a(n-4) - a(n-8) for n>7. - Vincenzo Librandi, Jan 19 2014
MAPLE
convert(sqrt(663), confrac, 30, cvgts): denom(cvgts); # Wesley Ivan Hurt, Dec 07 2013
MATHEMATICA
Denominator[Convergents[Sqrt[663], 30]] (* Vincenzo Librandi, Jan 19 2014 *)
PROG
(Magma) I:=[1, 1, 3, 4, 203, 207, 617, 824]; [n le 8 select I[n] else 206*Self(n-4)-Self(n-8): n in [1..40]]; // Vincenzo Librandi, Jan 19 2014
CROSSREFS
Sequence in context: A097172 A042081 A245456 * A012861 A349885 A042485
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Dec 06 2013
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 25 01:41 EDT 2024. Contains 374585 sequences. (Running on oeis4.)