A157475 a(n) = 512n + 16.

528, 1040, 1552, 2064, 2576, 3088, 3600, 4112, 4624, 5136, 5648, 6160, 6672, 7184, 7696, 8208, 8720, 9232, 9744, 10256, 10768, 11280, 11792, 12304, 12816, 13328, 13840, 14352, 14864, 15376, 15888, 16400, 16912, 17424, 17936, 18448, 18960

Offset

1,1

Comments

The identity (2048*n^2+128*n+1)^2-(16*n^2+n)*(512*n+16)^2=1 can be written as A157476(n)^2-A157474(n)*a(n)^2=1 (see also second comment in A157476). [rewritten by Bruno Berselli, Aug 22 2011]

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..10000

Vincenzo Librandi, X^2-AY^2=1

Index entries for linear recurrences with constant coefficients, signature (2,-1).

Formula

G.f.: 16*x*(33-x)/(1-x)^2. - Bruno Berselli, Aug 22 2011

a(1)=528, a(2)=1040, a(n) = 2*a(n-1)-a(n-2). - Harvey P. Dale, Dec 07 2011

Mathematica

512*Range[40]+16 (* or *) LinearRecurrence[{2, -1}, {528, 1040}, 40] (* Harvey P. Dale, Dec 07 2011 *)

Crossrefs

Cf. A157474, A157476.

Sequence in context: A158364 A232885 A085329 * A373285 A158365 A076580

Adjacent sequences: A157472 A157473 A157474 * A157476 A157477 A157478

Keyword

nonn,easy

Author

Vincenzo Librandi, Mar 01 2009

Status

approved