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A042303
Denominators of continued fraction convergents to sqrt(678).
2
1, 26, 1353, 35204, 1831961, 47666190, 2480473841, 64539986056, 3358559748753, 87387093453634, 4547487419337721, 118322059996234380, 6157294607223525481, 160207981847807896886, 8336972350693234163553, 216921489099871896149264
OFFSET
0,2
FORMULA
G.f.: -(x^2-26*x-1) / (x^4-1354*x^2+1). - Colin Barker, Dec 07 2013
a(n) = 1354*a(n-2) - a(n-4) for n>3. - Vincenzo Librandi, Jan 19 2014
MATHEMATICA
Denominator[Convergents[Sqrt[678], 30]] (* Vincenzo Librandi, Jan 19 2014 *)
LinearRecurrence[{0, 1354, 0, -1}, {1, 26, 1353, 35204}, 20] (* Harvey P. Dale, Nov 04 2024 *)
PROG
(Magma) I:=[1, 26, 1353, 35204]; [n le 4 select I[n] else 1354*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Jan 19 2014
CROSSREFS
Sequence in context: A220955 A106710 A114052 * A042300 A282884 A080163
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Dec 07 2013
STATUS
approved