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A031432
Least term in period of continued fraction for sqrt(n) is 8.
1
17, 66, 147, 260, 405, 582, 791, 1032, 1305, 1610, 1690, 1947, 2316, 2717, 3150, 3615, 4112, 4641, 4778, 5202, 5795, 6420, 7077, 7413, 7766, 8487, 9240, 10025, 10842, 11691, 12572, 13244, 13485, 14430, 14671, 15407, 16416, 16673, 17457
OFFSET
1,1
COMMENTS
16*m^2 + m for m >= 1 are terms of this sequence (see comment in A031742). The first term that is not of this form is a(11) = 1690. - Chai Wah Wu, Jun 19 2016
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 200 from Vincenzo Librandi)
MATHEMATICA
Select[Range[20000], !IntegerQ[Sqrt[#]] && Min[ContinuedFraction[Sqrt[#]][[2]]] == 8&] (* Vincenzo Librandi, Feb 07 2012 *)
CROSSREFS
Sequence in context: A044536 A115295 A065011 * A157474 A024215 A095071
KEYWORD
nonn
STATUS
approved