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!)
A195625 Denominators a(n) of Pythagorean approximations b(n)/a(n) to sqrt(1/2). 5

%I #13 Dec 07 2016 10:29:18

%S 1,4,756,435,7480,1760400,178342500,107770201,77071637784,85438755160,

%T 162402622743,150321171634588,314779738565193,1395140327976600,

%U 3899078438579384,26320772661145332,506075333191877232,6916169937061302541

%N Denominators a(n) of Pythagorean approximations b(n)/a(n) to sqrt(1/2).

%C See A195500 for a discussion and references.

%t r = Sqrt[1/2]; z = 30;

%t p[{f_, n_}] := (#1[[2]]/#1[[

%t 1]] &)[({2 #1[[1]] #1[[2]], #1[[1]]^2 - #1[[

%t 2]]^2} &)[({Numerator[#1], Denominator[#1]} &)[

%t Array[FromContinuedFraction[

%t ContinuedFraction[(#1 + Sqrt[1 + #1^2] &)[f], #1]] &, {n}]]]];

%t {a, b} = ({Denominator[#1], Numerator[#1]} &)[

%t p[{r, z}]] (* A195625, A195626 *)

%t Sqrt[a^2 + b^2] (* A195627 *)

%t (* _Peter J. C. Moses_, Sep 02 2011 *)

%Y Cf. A195500, A195626, A195627.

%K nonn,frac

%O 1,2

%A _Clark Kimberling_, Sep 22 2011

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 April 23 16:40 EDT 2024. Contains 371916 sequences. (Running on oeis4.)