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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A174779 y-values in the solution to x^2 - 42*y^2 = 1. 1
 0, 2, 52, 1350, 35048, 909898, 23622300, 613269902, 15921395152, 413343004050, 10730996710148, 278592571459798, 7232675861244600, 187770979820899802, 4874812799482150252, 126557361806715006750, 3285616594175108025248 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The corresponding values of x of this Pell equation are in A097308. LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..200 Index entries for linear recurrences with constant coefficients, signature (26,-1). FORMULA a(n) = 26*a(n-1)-a(n-2) with a(1)=0, a(2)=2. G.f.: 2*x^2/(1-26*x+x^2). MATHEMATICA LinearRecurrence[{26, -1}, {0, 2}, 30] With[{c=2*Sqrt[42]}, Table[-((13-c)^n-(13+c)^n)/c, {n, 0, 20}]]//Simplify (* Harvey P. Dale, Nov 05 2022 *) PROG (Magma) I:=[0, 2]; [n le 2 select I[n] else 26*Self(n-1)-Self(n-2): n in [1..20]]; CROSSREFS Cf. A097308. Sequence in context: A284767 A101930 A297756 * A215744 A099882 A216611 Adjacent sequences: A174776 A174777 A174778 * A174780 A174781 A174782 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Apr 15 2010 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.

Last modified August 12 15:11 EDT 2024. Contains 375113 sequences. (Running on oeis4.)