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A128873 Numerator of the continued fraction convergents of the decimal concatenation of the powers of 2. 0
0, 1, 84, 85, 1444, 1529, 85539, 87068, 172607, 259675, 691957, 1643589, 192991870, 194635459, 776898247, 1748431953, 9519058012, 11267489965, 99658977732, 210585445429, 8312491349463, 16835568144355, 25148059493818 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

FORMULA

The powers of 2 = 1,2,4,8,16,32,64,... are concatenated and then preceded by a decimal point to create the fraction N = .1248163264128... 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

PROG

(PARI) g(n) = f="."; for(x=0, n, a=concat(f, 2^x)); f=eval(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(numer", "); numer2=numer; denom2=denom; ) }

CROSSREFS

Sequence in context: A066689 A008898 A033404 * A095607 A068405 A045569

Adjacent sequences:  A128870 A128871 A128872 * A128874 A128875 A128876

KEYWORD

frac,nonn,base

AUTHOR

Cino Hilliard (hillcino368(AT)hotmail.com), Apr 18 2007

EXTENSIONS

Edited by Charles R Greathouse IV (charles.greathouse(AT)case.edu), Apr 25 2010

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Last modified February 18 00:14 EST 2012. Contains 206085 sequences.