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A042640
Numerators of continued fraction convergents to sqrt(850).
2
29, 175, 379, 2449, 142421, 856975, 1856371, 11995201, 697578029, 4197463375, 9092504779, 58752492049, 3416737043621, 20559174753775, 44535086551171, 287769694060801, 16735177342077629, 100698833746526575
OFFSET
0,1
LINKS
FORMULA
G.f.: (29 +175*x +379*x^2 +2449*x^3 +379*x^4 -175*x^5 +29*x^6 -x^7)/(1 -4898*x^4 +x^8). - Vincenzo Librandi, Nov 30 2013
a(n) = 4898*a(n-4) - a(n-8). - Vincenzo Librandi, Nov 30 2013
MATHEMATICA
Numerator[Convergents[Sqrt[850], 30]] (* Harvey P. Dale, Oct 27 2011 *)
CoefficientList[Series[(29 + 175 x + 379 x^2 + 2449 x^3 + 379 x^4 - 175 x^5 + 29 x^6 - x^7)/(1 - 4898 x^4 + x^8), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 30 2013 *)
PROG
(Magma) I:=[29, 175, 379, 2449, 142421, 856975, 1856371, 11995201]; [n le 8 select I[n] else 4898*Self(n-4)-Self(n-8): n in [1..30]]; // Vincenzo Librandi, Nov 30 2013
CROSSREFS
Cf. A042641.
Sequence in context: A033219 A142407 A183714 * A373540 A140573 A165613
KEYWORD
nonn,cofr,frac,easy
AUTHOR
STATUS
approved