A031609 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 21.

1033, 5674, 9106, 9685, 13577, 14045, 19213, 19769, 20333, 25189, 26794, 33413, 33778, 40361, 41165, 42797, 43625, 51517, 53341, 59093, 59578, 61538, 63029, 64033, 69269, 70321, 71381, 71914, 72986, 74066, 74609, 75154, 75701, 93257, 94477, 96941

Offset

1,1

Links

Table of n, a(n) for n=1..36.

Crossrefs

Subsequence of A003814.

Sequence in context: A168225 A282576 A122716 * A236804 A023063 A245680

Adjacent sequences: A031606 A031607 A031608 * A031610 A031611 A031612

Keyword

nonn

Author

David W. Wilson

Extensions

First term 442 removed by Georg Fischer, Jun 16 2019

Status

approved