The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A158252 289n^2 - 2n. 2
 287, 1152, 2595, 4616, 7215, 10392, 14147, 18480, 23391, 28880, 34947, 41592, 48815, 56616, 64995, 73952, 83487, 93600, 104291, 115560, 127407, 139832, 152835, 166416, 180575, 195312, 210627, 226520, 242991, 260040, 277667, 295872, 314655 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The identity (289*n-1)^2-(289*n^2-2*n)*(17)^2=1 can be written as A158253(n)^2-a(n)*(17)^2=1. LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..10000 Vincenzo Librandi, X^2-AY^2=1 E. J. Barbeau, Polynomial Excursions, Chapter 10: Diophantine equations (2010), pages 84-85 (row 15 in the first table at p. 85, case d(t) = t*(17^2*t-2)). Index entries for linear recurrences with constant coefficients, signature (3,-3,1). FORMULA a(n) = 3*a(n-1) -3*a(n-2) +a(n-3). G.f.: x*(-287-291*x)/(x-1)^3. MATHEMATICA LinearRecurrence[{3, -3, 1}, {287, 1152, 2595}, 50] PROG (Magma) I:=[287, 1152, 2595]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+1*Self(n-3): n in [1..50]]; (PARI) a(n) = 289*n^2 - 2*n. CROSSREFS Cf. A158253. Sequence in context: A157997 A063362 A159949 * A236869 A158287 A112245 Adjacent sequences: A158249 A158250 A158251 * A158253 A158254 A158255 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Mar 15 2009 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 May 24 06:28 EDT 2024. Contains 372772 sequences. (Running on oeis4.)