A201225 Values x for infinite sequence x^3-y^2 = d with decreasing coefficient r=sqrt(x)/d which tend to 1/(1350*sqrt(5))or infinity family of solutions Mordell curve with extension sqrt(5).

6100, 2305180, 748476100, 241118603980, 77641444770100, 25000340035616380, 8050032494909496100, 2592085474592828222380, 834643472994047002110100, 268752606222334691877221980, 86537504560185639786707316100, 27864807715774753485364243735180

Offset: 1

Author

Artur Jasinski, Nov 28 2011

Keywords

• nonn

Comments

a(1) = A200656(4) = A201047(4).

a(2) = A200656(36) = A201047(26).

All points in this sequence are extremal points (definition see A200656) and from these reason is subset of A200656 and primary (definition see A200656) and from these reason is subset of A201047.

Links

• Index entries for linear recurrences with constant coefficients, signature (341,-6138,6138,-341,1).

Crossrefs

Cf. A200216, A200656.

Programs

Mathematica

LinearRecurrence[{341,-6138,6138,-341,1},{6100,2305180,748476100,241118603980,77641444770100},20] (* Harvey P. Dale, Aug 17 2016 *)

Formula

G.f.: (20*(-305-11254*z+7424*z^2-346*z^3+z^4))/((-1+z)*(1- 322*z+z^2)*(1-18*z+z^2)).

a(n) = 341*a(n-1) - 6138*a(n-2) + 6138*a(n-3) - 341*a(n-4) + a(n-5).