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A031602 Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 14. 0
50, 1321, 2549, 2753, 4177, 4570, 6521, 6845, 12106, 15173, 15418, 19961, 23545, 26773, 27754, 28418, 28753, 29429, 31601, 31954, 32309, 32666, 33386, 33749, 34114, 34481, 35221, 36829, 40729, 41645, 42457, 45785, 46637, 47497, 48485, 51137, 53402 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
cfo14Q[n_]:=Module[{s=Sqrt[n], cf, len}, cf=If[IntegerQ[s], {}, ContinuedFraction[ s][[2]]]; len=Length[cf]; OddQ[len] && cf[[(len+1)/2]] == 14]; Select[Range[54000], cfo14Q] (* Harvey P. Dale, Dec 10 2013 *)
CROSSREFS
Sequence in context: A162492 A017713 A283311 * A231743 A140520 A114251
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected and definition clarified by Harvey P. Dale, Dec 10 2013
STATUS
approved

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Last modified July 22 22:03 EDT 2024. Contains 374544 sequences. (Running on oeis4.)