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A108575 Numbers k such that the continued fraction for sqrt(k) is multiplicative. 1
3, 7, 8, 13, 14, 15, 22, 23, 24, 32, 33, 34, 35, 44, 47, 48, 58, 59, 60, 62, 63, 74, 75, 78, 79, 80, 95, 96, 98, 99, 114, 119, 120, 135, 136, 138, 140, 141, 142, 143, 160, 162, 164, 167, 168, 185, 187, 189, 192, 194, 195, 215, 219, 220, 222, 223, 224, 248, 252, 254 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
m^2 - m < a(n) < m^2 for some m.
LINKS
EXAMPLE
The continued fraction for sqrt(7) is c = (2, 1, 1, 1, 4, 1, 1, 1, 4, ...) = A010121. If we index starting at 0, so that c(0) = 2, c is multiplicative (the value at c(0) is immaterial). Hence 7 is in the sequence.
CROSSREFS
Cf. A010121, A109054 (with squares included).
Sequence in context: A153030 A031425 A063657 * A153219 A264720 A215034
KEYWORD
nonn
AUTHOR
David W. Wilson, Jun 10 2005
STATUS
approved

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Last modified July 22 12:22 EDT 2024. Contains 374499 sequences. (Running on oeis4.)