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A042566
Numerators of continued fraction convergents to sqrt(812).
2
28, 57, 3220, 6497, 367052, 740601, 41840708, 84422017, 4769473660, 9623369337, 543678156532, 1096979682401, 61974540370988, 125046060424377, 7064553924136100, 14254153908696577, 805297172811144412
OFFSET
0,1
FORMULA
G.f.: (28 +57*x +28*x^2 -x^3)/(1 -114*x^2 +x^4). - Vincenzo Librandi, Nov 28 2013
a(n) = 114*a(n-2) - a(n-4). - Vincenzo Librandi, Nov 28 2013
MATHEMATICA
Numerator[Convergents[Sqrt[812], 30]] (* or *) CoefficientList[Series[(28 + 57 x + 28 x^2 - x^3)/(1 - 114 x^2 + x^4), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 28 2013 *)
LinearRecurrence[{0, 114, 0, -1}, {28, 57, 3220, 6497}, 20] (* Harvey P. Dale, Jun 03 2024 *)
PROG
(Magma) I:=[28, 57, 3220, 6497]; [n le 4 select I[n] else 114*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Nov 28 2013
CROSSREFS
Cf. A042567.
Sequence in context: A042564 A219920 A219216 * A132769 A329306 A329307
KEYWORD
nonn,cofr,frac,easy
AUTHOR
STATUS
approved