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A154131 Numbers n such that the fractional part of (4/3)^n is less than 1/n. 1
1, 4, 17, 1738, 1739, 12863, 15705, 109705, 174894, 289047, 720429, 2087694, 2087695, 4475944, 6968999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers n such that fract((4/3)^n) < 1/n, where fract(x) = x - floor(x).

The next term is greater than 3*10^8.

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

a(3)=17 since fract((4/3)^17) = 0.03273... < 1/17, but fract((4/3)^k) >= 1/k for 5 <= k <= 16.

MATHEMATICA

Select[Range[1000], N[FractionalPart[(4/3)^#], 100] < (1/#) &] (* G. C. Greubel, Sep 02 2016 *)

PROG

(PARI) isok(n) = frac((4/3)^n) < 1/n; \\ Michel Marcus, Sep 03 2016

CROSSREFS

Cf. A153662, A153670, A153702, A137994, A154139, A154147.

Cf. A002379, A064628.

Sequence in context: A277762 A337477 A041701 * A132554 A077275 A059903

Adjacent sequences:  A154128 A154129 A154130 * A154132 A154133 A154134

KEYWORD

nonn,more

AUTHOR

Hieronymus Fischer, Jan 11 2009

EXTENSIONS

a(10)-a(15) from Robert Gerbicz, Nov 21 2010

STATUS

approved

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Last modified September 19 20:55 EDT 2020. Contains 337182 sequences. (Running on oeis4.)