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A041469 Denominators of continued fraction convergents to sqrt(250). 2
1, 1, 5, 16, 53, 228, 281, 8658, 8939, 44414, 142181, 470957, 2026009, 2496966, 76934989, 79431955, 394662809, 1263420382, 4184923955, 18003116202, 22188040157, 683644320912, 705832361069, 3506973765188, 11226753656633, 37187234735087, 159975692596981 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,8886,0,0,0,0,0,0,1).

FORMULA

G.f.: -(x^12 -x^11 +5*x^10 -16*x^9 +53*x^8 -228*x^7 +281*x^6 +228*x^5 +53*x^4 +16*x^3 +5*x^2 +x +1) / (x^14 +8886*x^7 -1). - Colin Barker, Nov 18 2013

a(n) = 8886*a(n-7) + a(n-14) for n>13. - Vincenzo Librandi, Dec 18 2013

MATHEMATICA

Denominator[Convergents[Sqrt[250], 30]] (* Vincenzo Librandi, Dec 18 2013 *)

PROG

(MAGMA) I:=[1, 1, 5, 16, 53, 228, 281, 8658, 8939, 44414, 142181, 470957, 2026009, 2496966]; [n le 14 select I[n] else 8886*Self(n-7)+Self(n-14): n in [1..40]]; // Vincenzo Librandi, Dec 18 2013

CROSSREFS

Cf. A041468, A040234.

Sequence in context: A147536 A173871 A108300 * A089102 A098912 A299685

Adjacent sequences:  A041466 A041467 A041468 * A041470 A041471 A041472

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 18 2013

STATUS

approved

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Last modified March 7 14:00 EST 2021. Contains 341886 sequences. (Running on oeis4.)