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A065007
Integers for which the periodic part of the continued fraction for the square root of n begins with 4.
0
5, 18, 39, 52, 68, 85, 105, 126, 149, 150, 175, 202, 203, 232, 263, 264, 296, 297, 332, 333, 369, 370, 409, 410, 450, 451, 493, 494, 495, 539, 540, 586, 587, 588, 636, 637, 687, 688, 689, 740, 741, 742, 796, 797, 798, 853, 854, 855, 913, 914, 915, 974, 975
OFFSET
1,1
EXAMPLE
The continued fraction for the square root of 39 is 6, {4, 12}.
MATHEMATICA
Select[ Range[1000], First[ Last[ ContinuedFraction[ Sqrt[ # ]]]] == 4 & ]
CROSSREFS
Cf. A065005.
Sequence in context: A294090 A038346 A220243 * A031428 A007742 A225272
KEYWORD
easy,nonn
AUTHOR
Robert G. Wilson v, Nov 01 2001
STATUS
approved