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A124514
Numbers k for which 2*k-1, 4*k-1, 8*k-1, 16*k-1, 32*k-1, 64*k-1 and 128*k-1 are primes.
8
561330, 1082115, 1164735, 5128905, 5154945, 6157350, 7015155, 7072770, 9549960, 11551830, 12088065, 14421825, 18544365, 19099920, 21194760, 24580050, 25392720, 26277285, 31400085, 34359030, 42932385, 44087025, 47915595
OFFSET
1,1
LINKS
MATHEMATICA
Select[15*Range[3200000], And @@ PrimeQ /@ ({2, 4, 8, 16, 32, 64, 128}*# - 1) &] (* Ray Chandler, Nov 22 2006 *)
apQ[n_]:=AllTrue[NestList[2#&, 2n, 6]-1, PrimeQ]; Select[15*Range[ 32*10^5], apQ] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Dec 08 2019 *)
KEYWORD
nonn
AUTHOR
Artur Jasinski, Nov 04 2006
STATUS
approved