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A042197
Denominators of continued fraction convergents to sqrt(623).
2
1, 1, 24, 25, 1224, 1249, 29951, 31200, 1527551, 1558751, 37378824, 38937575, 1906382424, 1945319999, 46648742401, 48594062400, 2379163737601, 2427757800001, 58217593137624, 60645350937625, 2969194438143624, 3029839789081249, 72655509587012351
OFFSET
0,3
FORMULA
G.f.: -(x^2-x-1)*(x^4+25*x^2+1) / (x^8-1248*x^4+1). - Colin Barker, Dec 04 2013
a(n) = 1248*a(n-4) - a(n-8) for n>7. - Vincenzo Librandi, Jan 16 2014
MATHEMATICA
Denominator[Convergents[Sqrt[623], 30]] (* Harvey P. Dale, Jun 28 2012 *)
PROG
(Magma) I:=[1, 1, 24, 25, 1224, 1249, 29951, 31200]; [n le 8 select I[n] else 1248*Self(n-4)-Self(n-8): n in [1..30]]; // Vincenzo Librandi, Jan 16 2014
CROSSREFS
Sequence in context: A042192 A042194 A042196 * A042198 A002924 A241042
KEYWORD
nonn,cofr,frac,easy,less
AUTHOR
EXTENSIONS
More terms from Colin Barker, Dec 04 2013
STATUS
approved