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A042555
Denominators of continued fraction convergents to sqrt(806).
2
1, 2, 3, 5, 18, 41, 223, 933, 4888, 10709, 37015, 47724, 84739, 217202, 12248051, 24713304, 36961355, 61674659, 221985332, 505645323, 2750211947, 11506493111, 60282677502, 132071848115, 456498221847, 588570069962, 1045068291809, 2678706653580
OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12332790, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).
FORMULA
a(n) = 12332790*a(n-14) - a(n-28) for n > 27. - Vincenzo Librandi, Jan 25 2014
MATHEMATICA
Denominator[Convergents[Sqrt[806], 30]] (* Vincenzo Librandi, Jan 25 2014 *)
LinearRecurrence[{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12332790, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1}, {1, 2, 3, 5, 18, 41, 223, 933, 4888, 10709, 37015, 47724, 84739, 217202, 12248051, 24713304, 36961355, 61674659, 221985332, 505645323, 2750211947, 11506493111, 60282677502, 132071848115, 456498221847, 588570069962, 1045068291809, 2678706653580}, 30] (* Harvey P. Dale, May 26 2018 *)
PROG
(PARI) vector(30, i, contfracpnqn(contfrac(sqrt(806), i))[2, 1]) \\ Jinyuan Wang, Feb 28 2020
CROSSREFS
Sequence in context: A284530 A041293 A041713 * A041891 A042813 A128532
KEYWORD
nonn,frac,easy
EXTENSIONS
More terms from Vincenzo Librandi, Jan 25 2014
STATUS
approved