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A145336 Numbers x such that there exists n in N : (x+1)^3-x^3=43*n^2. 2
26, 893341, 30114541938, 1015161207853493, 34221084286626723946, 1153592750287025656383021, 38887611577954550590044930818, 1310901385139255150103388961508613, 44190485654156679532030691302410430266, 1489661270090720281885499453700866642775101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..10.

Index entries for linear recurrences with constant coefficients, signature (33711,-33711,1).

FORMULA

a(n+2) = 33710*a(n+1)-a(n)+16854.

a(n) = -(1/2)+(53/4)*{[16855+1484*sqrt(129)]^n+[16855-1484*sqrt(129)]^n}-(7/6)*sqrt(129)*{[16855-1484*sqrt(129)]^n- [16855+1484*sqrt(129)]^n} with n>=0. - Paolo P. Lava, Nov 25 2008

G.f.: x*(27*x^2-16855*x-26) / ((x-1)*(x^2-33710*x+1)). - Colin Barker, Oct 18 2014

EXAMPLE

a(1)=26 because the first relation is : 27^3-26^3=43*7^2.

PROG

(PARI) Vec(x*(27*x^2-16855*x-26)/((x-1)*(x^2-33710*x+1)) + O(x^20)) \\ Colin Barker, Oct 18 2014

CROSSREFS

Sequence in context: A265959 A112946 A034246 * A271246 A005084 A050454

Adjacent sequences:  A145333 A145334 A145335 * A145337 A145338 A145339

KEYWORD

easy,nonn

AUTHOR

Richard Choulet, Oct 08 2008

EXTENSIONS

Editing and more terms from Colin Barker, Oct 18 2014

STATUS

approved

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Last modified October 17 05:00 EDT 2021. Contains 348048 sequences. (Running on oeis4.)