|
| |
|
|
A031656
|
|
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 68.
|
|
0
|
|
|
|
29609, 57649, 94330, 94945, 96181, 141497, 143005, 262369, 336689, 420265, 422861, 425465, 515965, 521725, 524617, 621473, 724826, 728234, 729941, 733361, 735074, 738506, 743669, 847129, 850813, 988877, 992857, 1113986, 1118210
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
LINKS
|
Table of n, a(n) for n=1..29.
|
|
|
MATHEMATICA
|
cf68Q[n_]:=Module[{s=Sqrt[n], cf, len}, cf=If[IntegerQ[s], {1, 1}, ContinuedFraction[ s][[2]]]; len=Length[cf]; OddQ[len]&&cf[[(len+1)/2]] == 68]; Select[Range[1200, 112*10^4], cf68Q] (* Harvey P. Dale, Jan 27 2020 *)
|
|
|
CROSSREFS
|
Sequence in context: A251563 A022200 A234669 * A236734 A236317 A204601
Adjacent sequences: A031653 A031654 A031655 * A031657 A031658 A031659
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
David W. Wilson
|
|
|
EXTENSIONS
|
First term 4625 removed by Georg Fischer, Jun 16 2019
Definition modified by Harvey P. Dale, Jan 27 2020
|
|
|
STATUS
|
approved
|
| |
|
|
