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 A031614 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 26. 0
 170, 1609, 8513, 8698, 20857, 29753, 38641, 49573, 50914, 52273, 61865, 62861, 64877, 77725, 90529, 91733, 93554, 94778, 95393, 96629, 106901, 108209, 108866, 110849, 111514, 112181, 113521, 124633, 128893, 143725, 146765, 149837, 152941 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..33. MATHEMATICA cf26Q[n_]:=Module[{s=Sqrt[n], cf, len}, If[IntegerQ[s], cf={1, 1}, cf = ContinuedFraction[s][[2]]]; len=Length[cf]; OddQ[len]&&cf[[(len+1)/2]] == 26]; Select[Range[153000], cf26Q] (* Harvey P. Dale, Nov 23 2014 *) CROSSREFS Sequence in context: A262426 A250965 A250958 * A289648 A187520 A210784 Adjacent sequences: A031611 A031612 A031613 * A031615 A031616 A031617 KEYWORD nonn AUTHOR David W. Wilson EXTENSIONS Corrected by Harvey P. Dale, Nov 23 2014 STATUS approved

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Last modified December 6 18:41 EST 2023. Contains 367614 sequences. (Running on oeis4.)