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A041691
Denominators of continued fraction convergents to sqrt(365).
2
1, 9, 10, 19, 181, 6897, 62254, 69151, 131405, 1251796, 47699653, 430548673, 478248326, 908796999, 8657421317, 329890807045, 2977674684722, 3307565491767, 6285240176489, 59874727080168, 2281524869222873, 20593598550086025, 22875123419308898
OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 6916, 0, 0, 0, 0, 1).
FORMULA
G.f.: -(x^8 -9*x^7 +10*x^6 -19*x^5 +181*x^4 +19*x^3 +10*x^2 +9*x +1) / (x^10 +6916*x^5 -1). - Colin Barker, Nov 22 2013
a(n) = 6916*a(n-5) + a(n-10) for n>9. - Vincenzo Librandi, Dec 23 2013
MATHEMATICA
Denominator[Convergents[Sqrt[365], 30]] (* Vincenzo Librandi, Dec 23 2013 *)
LinearRecurrence[{0, 0, 0, 0, 6916, 0, 0, 0, 0, 1}, {1, 9, 10, 19, 181, 6897, 62254, 69151, 131405, 1251796}, 30] (* Harvey P. Dale, Jun 03 2019 *)
PROG
(Magma) I:=[1, 9, 10, 19, 181, 6897, 62254, 69151, 131405, 1251796]; [n le 10 select I[n] else 6916*Self(n-5)+Self(n-10): n in [1..40]]; // Vincenzo Librandi, Dec 23 2013
CROSSREFS
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 22 2013
STATUS
approved