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A042720
Numerators of continued fraction convergents to sqrt(890).
2
29, 30, 149, 179, 10531, 10710, 53371, 64081, 3770069, 3834150, 19106669, 22940819, 1349674171, 1372614990, 6840134131, 8212749121, 483179583149, 491392332270, 2448748912229, 2940141244499
OFFSET
0,1
LINKS
FORMULA
G.f.: (29 +30*x +149*x^2 +179*x^3 +149*x^4 -30*x^5 +29*x^6 -x^7)/(1 -358*x^4 +x^8). - Vincenzo Librandi, Dec 02 2013
a(n) = 358*a(n-4) - a(n-8). - Vincenzo Librandi, Dec 02 2013
MATHEMATICA
Numerator[Convergents[Sqrt[890], 30]] (* or *) CoefficientList[Series[(29 + 30 x + 149 x^2 + 179 x^3 + 149 x^4 - 30 x^5 + 29 x^6 - x^7)/(1 - 358 x^4 + x^8), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 02 2013 *)
PROG
(Magma) I:=[29, 30, 149, 179, 10531, 10710, 53371, 64081]; [n le 8 select I[n] else 358*Self(n-4)-Self(n-8): n in [1..30]]; // Vincenzo Librandi, Dec 02 2013
CROSSREFS
Cf. A042721.
Sequence in context: A042714 A042716 A042712 * A042718 A042722 A042724
KEYWORD
nonn,cofr,frac,easy
AUTHOR
STATUS
approved