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n for which floor((4/3)^n) is prime.
6

%I #21 Oct 02 2024 18:14:23

%S 3,4,6,7,9,10,11,12,38,42,59,96,154,171,211,313,465,563,1040,1176,

%T 1213,1431,1519,1987,2527,3033,4039,4209,4358,5109,5251,6642,19200,

%U 25275,42589,43025,49294,58585,66290,77458,80409,86533,94192,110452,115166,124470

%N n for which floor((4/3)^n) is prime.

%D R. K. Guy, Unsolved Problems in Number Theory, E19.

%H Giovanni Resta, <a href="/A070762/b070762.txt">Table of n, a(n) for n = 1..53</a> (terms < 400000)

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PowerFloors.html">Power Floors</a>

%t Do[ If[ PrimeQ[ Floor[(4/3)^n]], Print[n]], {n, 1, 17500}]

%t Select[Range[7000],PrimeQ[Floor[(4/3)^#]]&] (* The program generates the first 32 terms of the sequence. *) (* _Harvey P. Dale_, Oct 02 2024 *)

%Y Cf. A046038, A067905, A070761, A070759.

%K nonn

%O 1,1

%A _Eric W. Weisstein_, May 04 2002

%E Corrected by _Robert G. Wilson v_, Jan 15 2003

%E More terms from _Ryan Propper_, Jan 25 2008