login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A042061 Denominators of continued fraction convergents to sqrt(554). 2
1, 1, 2, 13, 54, 67, 121, 551, 3427, 3978, 7405, 344608, 352013, 696621, 4531739, 18823577, 23355316, 42178893, 192070888, 1194604221, 1386675109, 2581279330, 120125524289, 122706803619, 242832327908, 1579700771067, 6561635412176, 8141336183243 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,0,348586,0,0,0,0,0,0,0,0,0,0,1).

FORMULA

G.f.: -(x^20 -x^19 +2*x^18 -13*x^17 +54*x^16 -67*x^15 +121*x^14 -551*x^13 +3427*x^12 -3978*x^11 +7405*x^10 +3978*x^9 +3427*x^8 +551*x^7 +121*x^6 +67*x^5 +54*x^4 +13*x^3 +2*x^2 +x +1) / (x^22 +348586*x^11 -1). - Colin Barker, Nov 30 2013

MATHEMATICA

Denominator[Convergents[Sqrt[554], 30]] (* Harvey P. Dale, Jan 27 2013 *)

CoefficientList[Series[-(x^20 - x^19 + 2 x^18 - 13 x^17 + 54 x^16 - 67 x^15 + 121 x^14 - 551 x^13 + 3427 x^12 - 3978 x^11 + 7405 x^10 + 3978 x^9 + 3427 x^8 + 551 x^7 + 121 x^6 + 67 x^5 + 54 x^4 + 13 x^3 + 2 x^2 + x + 1)/(x^22 + 348586 x^11 - 1), {x, 0, 40}], x] (* Vincenzo Librandi, Jan 13 2014 *)

CROSSREFS

Cf. A042060, A040530.

Sequence in context: A177077 A144235 A180041 * A229736 A187560 A290721

Adjacent sequences:  A042058 A042059 A042060 * A042062 A042063 A042064

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 30 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 7 11:46 EDT 2020. Contains 336276 sequences. (Running on oeis4.)