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A042873
Denominators of continued fraction convergents to sqrt(968).
2
1, 8, 9, 62, 71, 630, 39131, 313678, 352809, 2430532, 2783341, 24697260, 1534013461, 12296804948, 13830818409, 95281715402, 109112533811, 968181985890, 60136395658991, 482059347257818, 542195742916809, 3735233804758672, 4277429547675481, 37954670186162520
OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 39202, 0, 0, 0, 0, 0, -1).
FORMULA
G.f.: -(x^10 - 8*x^9 + 9*x^8 - 62*x^7 + 71*x^6 - 630*x^5 - 71*x^4 - 62*x^3 - 9*x^2 - 8*x - 1) / ((x^2 - 6*x + 1)*(x^2 + 6*x + 1)*(x^4 - 6*x^3 + 35*x^2 - 6*x + 1)*(x^4 + 6*x^3 + 35*x^2 + 6*x + 1)). - Colin Barker, Dec 25 2013
a(n) = 39202*a(n-6) - a(n-12) for n > 11. - Vincenzo Librandi, Jan 31 2014
MATHEMATICA
Denominator[Convergents[Sqrt[968], 30]] (* Harvey P. Dale, Jun 12 2013 *)
PROG
(Magma) I:=[1, 8, 9, 62, 71, 630, 39131, 313678, 352809, 2430532, 2783341, 24697260]; [n le 12 select I[n] else 39202*Self(n-6)-Self(n-12): n in [1..30]]; // Vincenzo Librandi, Jan 31 2014
CROSSREFS
Sequence in context: A042847 A121330 A152189 * A342614 A033045 A025633
KEYWORD
nonn,frac,easy
EXTENSIONS
More terms from Colin Barker, Dec 25 2013
STATUS
approved