A188136 Primes p such that the period of the continued fraction of (1-sqrt(p))/2 has length 3 and p is not of the form k^2+1.

61, 317, 461, 557, 773, 1129, 1429, 1877, 1901, 4597, 5417, 6053, 8761, 10733, 11621, 13877, 15277, 16333, 17737, 18329, 23593, 30137, 41453, 45533, 51893, 59341, 70429, 74597, 74857, 80429, 86201, 92173, 94321, 94421, 100733, 104717

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..500 (terms 1..75 from Vincenzo Librandi)

Mathematica

Select[Prime[Range[100]], ! IntegerQ[Sqrt[# - 1]] && 3 == Length[ContinuedFraction[(1 + Sqrt[#])/2][[2]]] &]

Crossrefs

Cf. A002496, A146348.

Sequence in context: A234029 A142923 A154601 * A142953 A245763 A130117

Adjacent sequences: A188133 A188134 A188135 * A188137 A188138 A188139

Keyword

nonn

Author

Artur Jasinski, Mar 21 2011

Status

approved