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A041873
Denominators of continued fraction convergents to sqrt(458).
2
1, 2, 5, 212, 429, 1070, 45369, 91808, 228985, 9709178, 19647341, 49003860, 2077809461, 4204622782, 10487055025, 444660933832, 899808922689, 2244278779210, 95159517649509, 192563314078228, 480286145805965, 20364581437928758, 41209449021663481
OFFSET
0,2
FORMULA
G.f.: -(x^4 -2*x^3 +5*x^2 +2*x +1) / (x^6 +214*x^3 -1). - Colin Barker, Nov 26 2013
a(n) = 214*a(n-3) + a(n-6) for n>5. - Vincenzo Librandi, Dec 26 2013
MATHEMATICA
Denominator[Convergents[Sqrt[458], 30]] (* Vincenzo Librandi, Dec 26 2013 *)
PROG
(Magma) I:=[1, 2, 5, 212, 429, 1070]; [n le 6 select I[n] else 214*Self(n-3)+Self(n-6): n in [1..40]]; // Vincenzo Librandi, Dec 26 2013
CROSSREFS
Sequence in context: A027682 A096695 A084297 * A072118 A249180 A135724
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 26 2013
STATUS
approved