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A042467
Denominators of continued fraction convergents to sqrt(761).
2
1, 1, 2, 5, 12, 17, 29, 1583, 1612, 3195, 8002, 19199, 27201, 46400, 2532801, 2579201, 5112002, 12803205, 30718412, 43521617, 74240029, 4052483183, 4126723212, 8179206395, 20485136002, 49149478399, 69634614401, 118784092800, 6483975625601, 6602759718401
OFFSET
0,3
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,1600,0,0,0,0,0,0,1).
FORMULA
G.f.: -(x^12 - x^11 + 2*x^10 - 5*x^9 + 12*x^8 - 17*x^7 + 29*x^6 + 17*x^5 + 12*x^4 + 5*x^3 + 2*x^2 + x + 1) / (x^14 + 1600*x^7 - 1). - Colin Barker, Dec 14 2013
a(n) = 1600*a(n-7) + a(n-14). - Vincenzo Librandi, Dec 14 2013
MATHEMATICA
Denominator[Convergents[Sqrt[761], 30]] (* Vincenzo Librandi, Dec 14 2013 *)
LinearRecurrence[{0, 0, 0, 0, 0, 0, 1600, 0, 0, 0, 0, 0, 0, 1}, {1, 1, 2, 5, 12, 17, 29, 1583, 1612, 3195, 8002, 19199, 27201, 46400}, 30] (* Harvey P. Dale, Aug 23 2015 *)
PROG
(Magma) I:=[1, 1, 2, 5, 12, 17, 29, 1583, 1612, 3195, 8002, 19199, 27201, 46400]; [n le 14 select I[n] else 1600*Self(n-7)+Self(n-14): n in [1..40]]; // Vincenzo Librandi, Dec 14 2013
CROSSREFS
Sequence in context: A066267 A084122 A042143 * A024465 A041889 A055906
KEYWORD
nonn,frac,easy
EXTENSIONS
More terms from Colin Barker, Dec 14 2013
STATUS
approved