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%I #12 Mar 27 2020 09:02:08
%S 9549960,26277285,42932385,85864770,99239790,113183070,152596290,
%T 172159515,198479580,237059175,287482065,305192580,342533490,
%U 382203030,542591115,563002110,597825570,686106720,742227135,786875025,1135145760
%N Numbers k for which 2*k-1, 4*k-1, 8*k-1, 16*k-1, 32*k-1, 64*k-1, 128*k-1 and 256*k-1 are primes.
%H Amiram Eldar, <a href="/A124515/b124515.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[15*Range[76000000], And @@ PrimeQ /@ ({2, 4, 8, 16, 32, 64, 128, 256}*# - 1) &] (* _Ray Chandler_, Nov 22 2006 *)
%Y Cf. A006254, A124485, A124493, A124494, A124017, A125113, A124514, A124516.
%K nonn
%O 1,1
%A _Artur Jasinski_, Nov 04 2006
%E Extended by _Ray Chandler_, Nov 22 2006