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A097853
Period of continued fraction for square root of n (or 1 if n is a square).
6
1, 1, 2, 1, 1, 2, 4, 2, 1, 1, 2, 2, 5, 4, 2, 1, 1, 2, 6, 2, 6, 6, 4, 2, 1, 1, 2, 4, 5, 2, 8, 4, 4, 4, 2, 1, 1, 2, 2, 2, 3, 2, 10, 8, 6, 12, 4, 2, 1, 1, 2, 6, 5, 6, 4, 2, 6, 7, 6, 4, 11, 4, 2, 1, 1, 2, 10, 2, 8, 6, 8, 2, 7, 5, 4, 12, 6, 4, 4, 2, 1, 1, 2, 2, 5, 10, 2, 6, 5, 2, 8, 8, 10, 16, 4, 4, 11, 4, 2, 1, 1, 2, 12
OFFSET
1,3
EXAMPLE
1 is a square. 2 has continued fraction [1;2,2,2...], 3 has [1;1,2,1,2,1,2...]. - Georg Fischer, Jun 14 2019
MAPLE
a:= n-> `if`(issqr(n), 1, nops(numtheory[cfrac](
sqrt(n), 'periodic', 'quotients')[2])):
seq(a(n), n=1..120); # Alois P. Heinz, Jun 14 2019
CROSSREFS
See A003285, which is the main entry for this sequence.
Sequence in context: A297170 A359627 A127309 * A160266 A322134 A023504
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Sep 01 2004
STATUS
approved