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A065005
Integers for which the periodic part of the continued fraction for the square root of n begins with 2.
8
2, 6, 12, 19, 20, 29, 30, 41, 42, 54, 55, 56, 70, 71, 72, 88, 89, 90, 107, 108, 109, 110, 129, 130, 131, 132, 153, 154, 155, 156, 178, 179, 180, 181, 182, 206, 207, 208, 209, 210, 236, 237, 238, 239, 240, 267, 268, 269, 270, 271, 272, 301, 302, 303, 304, 305
OFFSET
1,1
EXAMPLE
The continued fraction for the square root of 12 is 3, {2, 6}.
MATHEMATICA
Select[ Range[500], First[ Last[ ContinuedFraction[ Sqrt[ # ]]]] == 2 & ]
CROSSREFS
Sequence in context: A178480 A053660 A104969 * A299016 A347472 A033154
KEYWORD
easy,nonn
AUTHOR
Robert G. Wilson v, Nov 01 2001
STATUS
approved