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A091448 Numbers k such that a1 > a2, where [a0,a1,a2,...] is the simple continued fraction of sqrt(k). 0
19, 28, 29, 52, 53, 54, 67, 70, 85, 86, 88, 103, 106, 107, 108, 124, 125, 126, 127, 129, 149, 151, 153, 172, 173, 174, 175, 176, 178, 179, 199, 201, 202, 204, 206, 207, 229, 232, 233, 234, 236, 237, 259, 261, 262, 263, 265, 267, 268, 292, 293, 294, 295, 296 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

sqrt(19) = [4;2,1,3,1,2,8,...], for which a1 = 2 > 1 = a2.

MATHEMATICA

Select[Range@300, Quiet[#[[1]]>#[[2]]&[Last@ContinuedFraction[Sqrt@#]]]&] (* Giorgos Kalogeropoulos, Jul 04 2021 *)

PROG

(PARI) for(k=2, 300, my(c=contfrac(sqrt(k))); if(#c>=3&&c[2]>c[3], print1(k, ", "))) \\ Hugo Pfoertner, Jul 04 2021

CROSSREFS

Cf. A000196, A091453.

Sequence in context: A298638 A291884 A173639 * A067777 A065207 A084364

Adjacent sequences:  A091445 A091446 A091447 * A091449 A091450 A091451

KEYWORD

nonn

AUTHOR

Clark Kimberling, Jan 10 2004

STATUS

approved

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Last modified August 5 20:48 EDT 2021. Contains 346488 sequences. (Running on oeis4.)