A042839 - OEIS

A042839

Denominators of continued fraction convergents to sqrt(950).

1, 1, 5, 6, 11, 17, 28, 45, 118, 163, 281, 444, 725, 1169, 5401, 6570, 399601, 406171, 2024285, 2430456, 4454741, 6885197, 11339938, 18225135, 47790208, 66015343, 113805551, 179820894, 293626445, 473447339, 2187415801, 2660863140

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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, 0, 0, 0, 0, 0, 0, 0, 0, 0, 405002, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).

FORMULA

a(n) = 405002*a(n-16) - a(n-32) for n>31. - Vincenzo Librandi, Jan 30 2014

MATHEMATICA

Denominator[Convergents[Sqrt[950], 30]] (* Vincenzo Librandi, Jan 30 2014 *)

LinearRecurrence[{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 405002, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1}, {1, 1, 5, 6, 11, 17, 28, 45, 118, 163, 281, 444, 725, 1169, 5401, 6570, 399601, 406171, 2024285, 2430456, 4454741, 6885197, 11339938, 18225135, 47790208, 66015343, 113805551, 179820894, 293626445, 473447339, 2187415801, 2660863140}, 40] (* Harvey P. Dale, Oct 08 2016 *)

PROG

(Magma) I:=[ /* copy and paste here the first terms up to 2660863140 */ ]; [n le 32 select I[n] else 405002*Self(n-16)-Self(n-32): n in [1..50]]; // Vincenzo Librandi, Jan 30 2014

CROSSREFS

Cf. A042838, A040919.

Sequence in context: A274283 A022095 A042531 * A041373 A041533 A042881

Adjacent sequences: A042836 A042837 A042838 * A042840 A042841 A042842

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Vincenzo Librandi, Jan 30 2014

STATUS

approved