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A031620 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 32. 0
13274, 21106, 21397, 21985, 44269, 58789, 75914, 77573, 78689, 93997, 96461, 114685, 116041, 118777, 120157, 139658, 143413, 162229, 163034, 163841, 167906, 169546, 170369, 196093, 219865, 227417, 229325, 249962, 250961, 252965, 253970 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
cf32Q[n_]:=Module[{s=Sqrt[n], cf, len}, cf=If[IntegerQ[s], {1, 1}, ContinuedFraction[ s][[2]]]; len=Length[cf]; OddQ[len]&&cf[[Floor[len/2]]]==cf[[Ceiling[len/2]]] == 32]; Select[ Range[254000], cf32Q] (* Harvey P. Dale, May 01 2022 *)
CROSSREFS
Subsequence of A003814.
Sequence in context: A184001 A345583 A345840 * A251339 A318252 A034625
KEYWORD
nonn
AUTHOR
EXTENSIONS
First term 1025 removed by Georg Fischer, Jun 16 2019
STATUS
approved

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Last modified April 20 22:14 EDT 2024. Contains 371848 sequences. (Running on oeis4.)