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A042863
Denominators of continued fraction convergents to sqrt(963).
2
1, 31, 1923, 59644, 3699851, 114755025, 7118511401, 220788608456, 13696012235673, 424797167914319, 26351120422923451, 817309530278541300, 50699541997692484051, 1572503111458745546881, 97545892452439916390673, 3025495169137096153657744
OFFSET
0,2
FORMULA
G.f.: -(x^2 - 31*x - 1) / (x^4 - 1924*x^2 + 1). - Colin Barker, Dec 25 2013
a(n) = 1924*a(n-2) - a(n-4) for n > 3. - Vincenzo Librandi, Dec 25 2013
MATHEMATICA
Denominator[Convergents[Sqrt[963], 30]] (* Vincenzo Librandi, Dec 25 2013 *)
PROG
(Magma) I:=[1, 31, 1923, 59644]; [n le 4 select I[n] else 1924*Self(n-2)-Self(n-4): n in [1..50]]; // Vincenzo Librandi, Dec 25 2013
CROSSREFS
Sequence in context: A338533 A055629 A131751 * A042860 A184488 A218352
KEYWORD
nonn,frac,easy
EXTENSIONS
Additional term from Colin Barker, Dec 25 2013
STATUS
approved