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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A195532 Denominators a(n) of Pythagorean approximations b(n)/a(n) to sqrt(5). 4
 8, 5, 84, 2400, 1691, 11480, 118455, 352692, 1401961, 1663145124, 1802526192, 15798984680, 297278169720, 1479041362764, 1551248530483, 42254295673488, 1445285680561323, 28154300465964144, 49087267967218280, 373205366478956820 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS See A195500 for a discussion and references. LINKS MATHEMATICA r = Sqrt[5]; z = 24; p[{f_,  n_}] := (#1[[2]]/#1[[       1]] &)[({2 #1[[1]] #1[[2]], #1[[1]]^2 - #1[[          2]]^2} &)[({Numerator[#1], Denominator[#1]} &)[      Array[FromContinuedFraction[         ContinuedFraction[(#1 + Sqrt[1 + #1^2] &)[f], #1]] &, {n}]]]]; {a, b} = ({Denominator[#1], Numerator[#1]} &)[   p[{r, z}]]  (* A195532, A195533 *) Sqrt[a^2 + b^2] (* A195534 *) (* by Peter J. C. Moses, Sep 02 2011 *) CROSSREFS Cf. A195500, A195533, A195534. Sequence in context: A038283 A317402 A317574 * A106287 A239862 A276688 Adjacent sequences:  A195529 A195530 A195531 * A195533 A195534 A195535 KEYWORD nonn,frac AUTHOR Clark Kimberling, Sep 20 2011 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.

Last modified February 25 06:46 EST 2020. Contains 332220 sequences. (Running on oeis4.)