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A041371
Denominators of continued fraction convergents to sqrt(200).
2
1, 7, 197, 1386, 39005, 274421, 7722793, 54333972, 1529074009, 10757852035, 302748930989, 2130000368958, 59942759261813, 421729315201649, 11868363584907985, 83500274409557544, 2349876047052519217, 16532632603777192063, 465263588952813896981
OFFSET
0,2
FORMULA
G.f.: -(x^2-7*x-1) / ((x^2-14*x-1)*(x^2+14*x-1)). - Colin Barker, Nov 16 2013
a(n) = 198*a(n-2) - a(n-4). - Vincenzo Librandi, Dec 16 2013
MATHEMATICA
Denominator[Convergents[Sqrt[200], 30]] (* Vincenzo Librandi, Dec 16 2013 *)
PROG
(Magma) I:=[1, 7, 197, 1386]; [n le 4 select I[n] else 198*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Dec 16 2013
CROSSREFS
Sequence in context: A156359 A128786 A034835 * A136675 A099198 A365988
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 16 2013
STATUS
approved