%I #34 Nov 12 2023 05:59:16
%S 4,1,2,4,2,1,8,1,2,4,2,1,8,1,2,4,2,1,8,1,2,4,2,1,8,1,2,4,2,1,8,1,2,4,
%T 2,1,8,1,2,4,2,1,8,1,2,4,2,1,8,1,2,4,2,1,8,1,2,4,2,1,8,1,2,4,2,1,8,1,
%U 2,4,2,1,8,1,2,4,2,1,8,1,2
%N Continued fraction for sqrt(22).
%H Harry J. Smith, <a href="/A010126/b010126.txt">Table of n, a(n) for n = 0..20000</a>
%H G. Xiao, <a href="http://wims.unice.fr/~wims/en_tool~number~contfrac.en.html">Contfrac</a>.
%H <a href="/index/Con#confC">Index entries for continued fractions for constants</a>.
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,1).
%F From _Amiram Eldar_, Nov 12 2023: (Start)
%F Multiplicative with a(2^e) = 2, a(3^e) = 4, and a(p^e) = 1 for p >= 5.
%F Dirichlet g.f.: zeta(s) * (1 + 1/2^s) * (1 + 1/3^(s-1)). (End)
%e 4.690415759823429554565630113... = 4 + 1/(1 + 1/(2 + 1/(4 + 1/(2 + ...)))). - _Harry J. Smith_, Jun 03 2009
%t ContinuedFraction[Sqrt[22],300] (* _Vladimir Joseph Stephan Orlovsky_, Mar 05 2011 *)
%t PadRight[{4},120,{8,1,2,4,2,1}] (* _Harvey P. Dale_, Jul 02 2019 *)
%o (PARI) { allocatemem(932245000); default(realprecision, 18000); x=contfrac(sqrt(22)); for (n=0, 20000, write("b010126.txt", n, " ", x[n+1])); } \\ _Harry J. Smith_, Jun 03 2009
%Y Cf. A041034/A041035 (convergents), A248250 (Egyptian fraction), A010478 (decimal expansion).
%K nonn,cofr,easy,mult
%O 0,1
%A _N. J. A. Sloane_