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A073834 Denominators of b(n) where b(1) = 1, b(i) = b(i-1) + 1/b(i-1). 4
1, 1, 2, 10, 290, 272890, 264588959090, 268440386798659418988490, 295105036840595214385430531020664149472669868290, 377908709746050392481071609609580527436122569261424131112048023467330784739529329885668846964890 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
a(n) is also the denominator of the fractional chromatic number of the Mycielski graph M_n - Eric W. Weisstein, Mar 05 2011
REFERENCES
H. L. Montgomery, Ten Lectures on the Interface Between Analytic Number Theory and Harmonic Analysis, Amer. Math. Soc., 1996, p. 187.
D. J. Newman, A Problem Seminar, Springer; see Problem #60.
J. H. Silverman, The arithmetic of dynamical systems, Springer, 2007, see p. 113 Table 3.1
LINKS
Eric Weisstein's World of Mathematics, Fractional Chromatic Number
Eric Weisstein's World of Mathematics, Mycielski Graph
MATHEMATICA
f[n_]:=n+1/n; Prepend[Denominator[NestList[f, 2, 9]], 1] (* Vladimir Joseph Stephan Orlovsky, Nov 19 2010 *)
Denominator[NestList[# + 1/# &, 1, 10]] (* Eric W. Weisstein, Mar 05 2011 *)
PROG
(PARI) {a(n) = local(x, y); if( n<1, 0, if( n<3, n, x = a(n-2)^2; y = a(n-1); y*y + x * (y - x)))} /* Michael Somos, Mar 05 2012 */
CROSSREFS
See A073833 for numerators.
Sequence in context: A098706 A143249 A161181 * A321267 A111837 A092123
KEYWORD
frac,nonn
AUTHOR
Alex Fink, Aug 12 2002
STATUS
approved

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Last modified March 19 03:21 EDT 2024. Contains 370952 sequences. (Running on oeis4.)