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A153678 Numbers k such that the fractional part of (1024/1000)^k is less than 1/k. 12
1, 2, 3, 4, 5, 6, 585, 1164, 1707, 522271, 3675376, 3906074, 9424094 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers k such that fract((1024/1000)^k) < 1/k, where fract(x) = x-floor(x).

The next such number must be greater than 5*10^5.

a(14) > 10^7. Robert Price, Mar 16 2019

LINKS

Table of n, a(n) for n=1..13.

EXAMPLE

a(7) = 585 since fract((1024/1000)^585) = 0.00139... < 1/585, but fract((1024/1000)^k) >= 1/k for 7 <= k <= 584.

MATHEMATICA

Select[Range[2000], FractionalPart[(1024/1000)^#] < (1/#) &] (* G. C. Greubel, Aug 24 2016 *)

PROG

(PARI) isok(n) = frac((1024/1000)^n) < 1/n \\ Michel Marcus, Aug 06 2013

CROSSREFS

Cf. A153662, A153670, A153682, A154130, A153686, A153694, A153702, A153710, A153718.

Sequence in context: A004879 A062943 A004890 * A004901 A004912 A292125

Adjacent sequences:  A153675 A153676 A153677 * A153679 A153680 A153681

KEYWORD

nonn,more

AUTHOR

Hieronymus Fischer, Jan 06 2009

EXTENSIONS

a(10)-a(13) from Robert Price, Mar 16 2019

Corrected Mathematica program by Robert Price, Mar 16 2019

STATUS

approved

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Last modified October 23 14:54 EDT 2019. Contains 328345 sequences. (Running on oeis4.)