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A157435 64n + 632. 3
696, 760, 824, 888, 952, 1016, 1080, 1144, 1208, 1272, 1336, 1400, 1464, 1528, 1592, 1656, 1720, 1784, 1848, 1912, 1976, 2040, 2104, 2168, 2232, 2296, 2360, 2424, 2488, 2552, 2616, 2680, 2744, 2808, 2872, 2936, 3000, 3064, 3128, 3192, 3256, 3320, 3384 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The identity (128*n^2+2528*n+12481)^2-(4*n^2+79*n+390)*(64*n+632)^2=1 can be written as A157436(n)^2-A157434(n)* a(n)^2=1.

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

a(n) = 2*a(n-1)-a(n-2).

G.f.: x*(696-632x)/(1-x)^2.

MATHEMATICA

LinearRecurrence[{2, -1}, {696, 760}, 50]

PROG

(Magma) I:=[696, 760]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..50]];

(PARI) a(n) = 64*n + 632.

CROSSREFS

Cf. A157434, A157436.

Sequence in context: A048925 A251367 A221418 * A048426 A209731 A222782

Adjacent sequences:  A157432 A157433 A157434 * A157436 A157437 A157438

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Mar 01 2009

STATUS

approved

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Last modified September 26 23:44 EDT 2022. Contains 357051 sequences. (Running on oeis4.)