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A041329
Denominators of continued fraction convergents to sqrt(178).
2
1, 2, 3, 38, 41, 120, 3161, 6442, 9603, 121678, 131281, 384240, 10121521, 20627282, 30748803, 389612918, 420361721, 1230336360, 32409107081, 66048550522, 98457657603, 1247540441758, 1345998099361, 3939536640480, 103773950751841, 211487438144162
OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,3202,0,0,0,0,0,-1).
FORMULA
G.f.: -(x^10-2*x^9+3*x^8-38*x^7+41*x^6-120*x^5-41*x^4-38*x^3-3*x^2-2*x-1) / (x^12-3202*x^6+1). - Colin Barker, Nov 15 2013
a(n) = 3202*a(n-6) - a(n-12). - Vincenzo Librandi, Dec 15 2013
MATHEMATICA
Denominator[Convergents[Sqrt[178], 30]] (* Vincenzo Librandi, Dec 15 2013 *)
PROG
(Magma) I:=[1, 2, 3, 38, 41, 120, 3161, 6442, 9603, 121678, 131281, 384240]; [n le 12 select I[n] else 3202*Self(n-6)-Self(n-12): n in [1..40]]; // Vincenzo Librandi, Dec 15 2013
CROSSREFS
Sequence in context: A245061 A270587 A119448 * A060813 A039820 A331204
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 15 2013
STATUS
approved