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A145207 Numbers n such that there exists x in N with (x+67)^3-x^3=n^2. 1
139159, 143360071051, 147688111595890531, 152146815684827106059839, 156740128050204348280189648879, 161472112515887870739083747272597171, 166346955592585785428646481254476689943611 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..7.

Index entries for linear recurrences with constant coefficients, signature (1030190,-1).

FORMULA

a(n+2) = 1030190*a(n+1)-a(n).

a(n) = 4489*A145210(n). - Colin Barker, Oct 19 2014

G.f.: -139159*x*(x-1) / (x^2-1030190*x+1). - Colin Barker, Oct 19 2014

EXAMPLE

a(1)= 139159 because the first relation is : (9782+67)^3-9782^3=139159^2.

MATHEMATICA

LinearRecurrence[{1030190, -1}, {139159, 143360071051}, 20] (* Harvey P. Dale, Jul 11 2018 *)

PROG

(PARI) Vec(-139159*x*(x-1)/(x^2-1030190*x+1) + O(x^20)) \\ Colin Barker, Oct 19 2014

CROSSREFS

Sequence in context: A236063 A234821 A221669 * A236745 A205213 A206221

Adjacent sequences:  A145204 A145205 A145206 * A145208 A145209 A145210

KEYWORD

easy,nonn

AUTHOR

Richard Choulet, Oct 04 2008

STATUS

approved

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Last modified January 29 01:49 EST 2020. Contains 331328 sequences. (Running on oeis4.)