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A042015
Denominators of continued fraction convergents to sqrt(531).
2
1, 23, 1059, 24380, 1122539, 25842777, 1189890281, 27393319240, 1261282575321, 29036892551623, 1336958339949979, 30779078711401140, 1417174579064402419, 32625794397192656777, 1502203716849926614161, 34583311281945504782480, 1592334522686343146608241
OFFSET
0,2
FORMULA
G.f.: -(x^2-23*x-1) / (x^4-1060*x^2+1). - Colin Barker, Nov 29 2013
a(n) = 1060*a(n-2) - a(n-4) for n>3. - Vincenzo Librandi, Jan 12 2014
MATHEMATICA
Denominator[Convergents[Sqrt[531], 40]] (* Vincenzo Librandi, Jan 12 2014 *)
LinearRecurrence[{0, 1060, 0, -1}, {1, 23, 1059, 24380}, 20] (* Harvey P. Dale, Oct 06 2023 *)
PROG
(Magma) I:=[1, 23, 1059, 24380]; [n le 4 select I[n] else 1060*Self(n-2)-Self(n-4): n in [1..20]]; // Vincenzo Librandi, Jan 12 2014
CROSSREFS
Sequence in context: A130551 A069479 A174748 * A042012 A128404 A126741
KEYWORD
nonn,frac,easy,less
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 29 2013
STATUS
approved