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A042689
Denominators of continued fraction convergents to sqrt(874).
2
1, 1, 2, 7, 16, 55, 71, 126, 7379, 7505, 14884, 52157, 119198, 409751, 528949, 938700, 54973549, 55912249, 110885798, 388569643, 888025084, 3052644895, 3940669979, 6993314874, 409552932671, 416546247545, 826099180216, 2894843788193, 6615786756602
OFFSET
0,3
LINKS
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 7450, 0, 0, 0, 0, 0, 0, 0, -1).
FORMULA
G.f.: -(x^14 -x^13 +2*x^12 -7*x^11 +16*x^10 -55*x^9 +71*x^8 -126*x^7 -71*x^6 -55*x^5 -16*x^4 -7*x^3 -2*x^2 -x -1) / (x^16 -7450*x^8 +1). - Colin Barker, Dec 21 2013
a(n) = 7450*a(n-8) - a(n-16) for n>15. - Vincenzo Librandi, Dec 21 2013
MATHEMATICA
Denominator[Convergents[Sqrt[874], 30]] (* Vincenzo Librandi Dec 21 2013 *)
PROG
(Magma) I:=[1, 1, 2, 7, 16, 55, 71, 126, 7379, 7505, 14884, 52157, 119198, 409751, 528949, 938700]; [n le 16 select I[n] else 7450*Self(n-8)-Self(n-16): n in [1..70]]; // Vincenzo Librandi, Dec 21 2013
CROSSREFS
Sequence in context: A084079 A286848 A239425 * A073998 A129444 A079815
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Dec 21 2013
STATUS
approved