A128872 - OEIS

%I #4 Oct 01 2013 21:35:21

%S 1,89,79211,2138786,2217997,179578546,181796543,361375089,543171632,

%T 904546721,2352265074,3256811795,25149947639,78706654712,103856602351,

%U 182563257063,651546373540,1485656004143,2137202377683,12171667892558

%N Denominator of the continued fraction convergents of the decimal concatenation of the Fibonacci numbers.

%F The Fibonacci numbers 0,1,1,2,3,5,8,13... are concatenated and then preceded by a decimal point to create the fraction N = .01123581321... This number is then evaluated with n=0,m=steps to iterate,x = N, a(0)=floor(N) using the loop: do a(n)=floor(x) x=1/(x-a(n)) n=n+1 loop until n=m

%o (PARI) fib(n) = a=".";for(x=0,n,a=concat(a,Str(fibonacci(x))));a=eval(a) cfrac2(m,f) = { default(realprecision,1000); cf = vector(1000); cf = contfrac(f); for(m1=0,m-1, r=cf[m1+1]; forstep(n=m1,1,-1, r = 1/r; r+=cf[n];); numer=numerator(r); denom=denominator(r); print1(denom","); numer2=numer;denom2=denom; ) }

%K frac,nonn,base

%O 0,2

%A _Cino Hilliard_, Apr 18 2007

%E Edited by _Charles R Greathouse IV_, Apr 25 2010