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A042110
Numerators of continued fraction convergents to sqrt(580).
2
24, 289, 13896, 167041, 8031864, 96549409, 4642403496, 55805391361, 2683301188824, 32255419657249, 1550943444736776, 18643576756498561, 896442627756667704, 10775955109836511009, 518142287899909196136
OFFSET
0,1
FORMULA
G.f.: (24 + 289*x + 24*x^2 - x^3)/(1 - 578*x^2 + x^4). - Vincenzo Librandi, Nov 16 2013
a(n) = 578*a(n-2) - a(n-4). - Vincenzo Librandi, Nov 16 2013
MATHEMATICA
Numerator[Convergents[Sqrt[580], 30]] (* or *) CoefficientList[Series[(24 + 289 x + 24 x^2 - x^3)/(1 - 578 x^2 + x^4), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 16 2013 *)
LinearRecurrence[{0, 578, 0, -1}, {24, 289, 13896, 167041}, 20] (* Harvey P. Dale, Jun 21 2021 *)
PROG
(Magma) I:=[24, 289, 13896, 167041]; [n le 4 select I[n] else 578*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Nov 16 2013
CROSSREFS
Cf. A042111.
Sequence in context: A035707 A035475 A288458 * A282993 A295272 A369469
KEYWORD
nonn,cofr,frac,easy,less
AUTHOR
STATUS
approved