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A041513
Denominators of continued fraction convergents to sqrt(273).
2
1, 1, 2, 21, 23, 44, 1431, 1475, 2906, 30535, 33441, 63976, 2080673, 2144649, 4225322, 44397869, 48623191, 93021060, 3025297111, 3118318171, 6143615282, 64554470991, 70698086273, 135252557264, 4398779918721, 4534032475985, 8932812394706, 93862156423045
OFFSET
0,3
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,1454,0,0,0,0,0,-1).
FORMULA
G.f.: -(x^4-x^3+2*x^2+x+1)*(x^6-22*x^3-1) / (x^12-1454*x^6+1). - Colin Barker, Nov 18 2013
a(n) = 1454*a(n-6) - a(n-12) for n>11. - Vincenzo Librandi, Dec 19 2013
MATHEMATICA
Denominator[Convergents[Sqrt[273], 30]] (* Vincenzo Librandi, Dec 19 2013 *)
LinearRecurrence[{0, 0, 0, 0, 0, 1454, 0, 0, 0, 0, 0, -1}, {1, 1, 2, 21, 23, 44, 1431, 1475, 2906, 30535, 33441, 63976}, 30] (* Harvey P. Dale, Jun 15 2021 *)
PROG
(Magma) I:=[1, 1, 2, 21, 23, 44, 1431, 1475, 2906, 30535, 33441, 63976]; [n le 12 select I[n] else 1454*Self(n-6)-Self(n-12): n in [1..30]]; // Vincenzo Librandi, Dec 19 2013
CROSSREFS
Sequence in context: A233135 A322925 A294116 * A135053 A042565 A079907
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 18 2013
STATUS
approved