A350980 a(0) = 17, a(1) = 4700, thereafter a(n) = 254*a(n-1) - a(n-2) + 378.

17, 4700, 1194161, 303312572, 77040199505, 19567907362076, 4970171429768177, 1262403975253755260, 320645639543024068241, 81442730039952859578332, 20686132784508483308828465, 5254196284535114807582852156, 1334545170139134652642735619537, 338969219019055666656447264510620

Offset

0,1

Comments

Arises in studying the equation x^3 - 7*y^2 = 1.

References

P.-F. Teilhet, Query 2228, L'Intermédiaire des Mathématiciens, 11 (1904), 44-45.

Links

Table of n, a(n) for n=0..13.

Index entries for linear recurrences with constant coefficients, signature (255,-255,1).

Formula

From Chai Wah Wu, Mar 07 2022: (Start)

a(n) = 255*a(n-1) - 255*a(n-2) + a(n-3) for n > 3.

G.f.: (4*x^2 - 365*x - 17)/((x - 1)*(x^2 - 254*x + 1)). (End)

Crossrefs

Cf. A350979, A350981.

Sequence in context: A194015 A015058 A015034 * A161583 A013722 A357419

Adjacent sequences: A350977 A350978 A350979 * A350981 A350982 A350983

Keyword

nonn,easy

Author

N. J. A. Sloane, Mar 06 2022

Status

approved