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A042321
Denominators of continued fraction convergents to sqrt(687).
2
1, 4, 5, 14, 19, 318, 337, 992, 1329, 6308, 329345, 1323688, 1653033, 4629754, 6282787, 105154346, 111437133, 328028612, 439465745, 2085891592, 108905828529, 437709205708, 546615034237, 1530939274182, 2077554308419, 34771808208886, 36849362517305
OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 330674, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).
FORMULA
G.f.: -(x^18 -4*x^17 +5*x^16 -14*x^15 +19*x^14 -318*x^13 +337*x^12 -992*x^11 +1329*x^10 -6308*x^9 -1329*x^8 -992*x^7 -337*x^6 -318*x^5 -19*x^4 -14*x^3 -5*x^2 -4*x -1) / (x^20 -330674*x^10 +1). - Colin Barker, Dec 07 2013
a(n) = 330674*a(n-10) - a(n-20). - Wesley Ivan Hurt, Jun 26 2022
MATHEMATICA
Denominator[Convergents[Sqrt[687], 30]] (* Vincenzo Librandi, Jan 20 2014 *)
CROSSREFS
Sequence in context: A300278 A129720 A041089 * A050164 A188021 A191790
KEYWORD
nonn,frac,easy
EXTENSIONS
More terms from Colin Barker, Dec 07 2013
STATUS
approved