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A010122
Continued fraction for sqrt(13).
9
3, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6, 1, 1, 1, 1, 6
OFFSET
0,1
COMMENTS
Eventual period is (1, 1, 1, 1, 6). - Zak Seidov, Mar 05 2011
Decimal expansion of 311113/999990. - Elmo R. Oliveira, Oct 14 2025
REFERENCES
Albert H. Beiler, Recreations in the theory of numbers, New York, Dover, (2nd ed.) 1966. See Table 96 at p. 264.
Florian Cajori, A History of Mathematical Notations, Dover edition (2012), par. 428.
Harold Davenport, The Higher Arithmetic, Cambridge University Press, 8th ed., 2008, p. 97.
FORMULA
From Amiram Eldar, Nov 12 2023: (Start)
Multiplicative with a(5^e) = 6, and a(p^e) = 1 for p != 5.
Dirichlet g.f.: zeta(s) * (1 + 1/5^(s-1)). (End)
G.f.: (3 + x + x^2 + x^3 + x^4 + 3*x^5)/(1 - x^5). - Stefano Spezia, Aug 17 2024
EXAMPLE
3.605551275463989293119221267... = 3 + 1/(1 + 1/(1 + 1/(1 + 1/(1 + ...)))). - Harry J. Smith, Jun 02 2009
MATHEMATICA
ContinuedFraction[Sqrt[13], 300] (* Vladimir Joseph Stephan Orlovsky, Mar 05 2011 *)
PROG
(PARI) { allocatemem(932245000); default(realprecision, 13000); x=contfrac(sqrt(13)); for (n=0, 20000, write("b010122.txt", n, " ", x[n+1])); } \\ Harry J. Smith, Jun 02 2009
CROSSREFS
Cf. A010470 (decimal expansion), A041018/A041019 (convergents), A248242 (Egyptian fraction).
Sequence in context: A140750 A028264 A208673 * A220693 A208615 A058663
KEYWORD
nonn,cofr,easy,mult
STATUS
approved